**5. Microbial pathogenic pollution**

The microbiological activities are of great importance for many ecological processes in the marine ecosystem. Their functions are essential for the maintenance of biogeochemical cycles required for the maintenance of life [48]. Marine ecosystem provides a natural habitat for a range of microbial pathogens such as bacteria, viruses and parasites. Some pathogens inhabit the water, while other can live attached to particles or inside of marine organisms.

High concentrations of these microbes within coastal waters should indicate that the water or even seafood may be contaminated by human waste [1, 49]. However, the use of indicator microbes to test the quality coast waters for recreation and sea food consumption has been questioned, particularly in the subtropical and tropical marine environments, mainly in areas with no point source of contamination identified [1, 50]. An example is bacteria species from the families Aeromonadaceae and Vibrionaceae that are naturally inhabitants of the marine environments. Many species of this family are not related with fecal contamination of coastal waters; therefore, the use of enteric bacteria as indicators of microbiological water quality is strongly limited [1, 50]. *Vibrio* species, especially *V. cholerae, V. parahaemolyticus*, and *V. vulnificus*, are frequently associated with infectious diseases through the ingestion of shellfish or even fish [42, 50, 51]. *Vibrio* and *Aeromonas* species are clinically important for humans and biodiversity health, causing gastroenteritis of infections through the open wounds resulting in septicemia. A large number of people worldwide have been impacted by the infections of pathogenic microbes in coastal waters. More than 170 million cases of respiratory and enteric impairments associated with recreation and seafood consumption coastal waters contaminated with infectious microbes have been reported [52]. In the United States (USA) 33% of shellfish harvesting waters are impacted by micropathogens. Currently, 62% of the coastal beaches of the Rio de Janeiro state (Brazil) are classified as inappropriate for recreation, principally due to contamination with fecal bacteria. In addition, 20,300 recreational beach warnings were reported in USA in 2008 due to the fecal microbe presence in coastal waters [53].

270 Biodiversity Conservation and Utilization in a Diverse World

cyanobacteria potentially hazardous.

**5. Microbial pathogenic pollution** 

organisms.

mainly in the extractive fishing, aquaculture and tourism [1, 4, 43].

copepods are capable of carrying the bacteria *Vibrio cholerae*, feed of algal blooms. Therefore, these blooms can lead to spread of cholera and outbreaks associated with the frequency of flooding and extreme events [46]. Shuval [40] estimated that marine biotoxins associated mainly with blooms of toxic algae cause an estimated 100,000 to 200,000 cases of severe poisoning annually worldwide and approximately 10,000 to 20,000 deaths and a similar number of very severe cases with neurological sequel, such as paralysis. Furthermore, HABs events can produce mass deaths of marine organisms and cause heavy economic losses,

In Brazilian coastal water, toxic algae bloom has caused impacts on biodiversity and resulting economic impairment, principally on aquaculture and fishery activities. In Baía de Todos os Santos, Bahia state (Brazilian coast), a massive mortality of fishes and shellfishes was registered in 2007. About 50 tons of fishes and shellfishes were killed, which resulted in negative consequences for fisheries and aquaculture, due to the prohibition to commercialize organisms for consumption from this contaminated area. Similarly, in Florianópolis, Santa Catarina state, southern Brazil, an harmful algal bloom of pseudonitzschia were identified, resulting in a preventing official measure to protect the population against the effect caused by the event. Despite the identification of harmful algal blooms in coastal regions of Brazil and their association with impacts on biodiversity, few studies have focused to understand the impacts on human health. However, cases of human death have been registered associated with consumption of water from reservoirs with bloom of

A drastic epidemic gastroenteritis outbreak was registered in Itaparica, region of Bahia State associated with the flooding of a Dam reservoir in 1988. From about 2,000 gastroenteritis cases identified, 88 resulted in death along a period of 42 days. Bacterial, toxicological and virological analises were conducted in fecal and blood samples from the patients, and drinking water was examined for microorganisms and metals. Clinical results were also reviewed to understand and identify the etiologic agent. The laboratory analyses indicated that the source of the epidemiology was water from the Dam, which revealed the presence of high concentrations of toxin produced by cyanobacteria (genus *Anabaena* and *Microcystis*). The cases of infectious disease were restricted to the areas supplied by drinking water from the dam. Also in 1996, 54 fatalities were recorded in Caruaru (Pernambuco state, northeastern Brazil) in hospitalized patients with chronic renal failure. During hemodialysis

sessions, the patients received untreated water contaminated with cyanobacteria.

The microbiological activities are of great importance for many ecological processes in the marine ecosystem. Their functions are essential for the maintenance of biogeochemical cycles required for the maintenance of life [48]. Marine ecosystem provides a natural habitat for a range of microbial pathogens such as bacteria, viruses and parasites. Some pathogens inhabit the water, while other can live attached to particles or inside of marine In Table 1 we present some results of bacteriological surveys (Aeromonadaceae and Vibrionacea species) that have been carried out with many specimens of marine mammals, seabirds and sea turtles from Brazilian coast. The microbiological samples were collected during a long term beach monitoring program for research and conservation of marine mammals, seabirds and sea turtles. This monitoring program has been conducted since 1999 by the GEMM-Lagos from the National School of Public Health (ENSP/FIOCRUZ). The bacteriological analyses were conducted in the *National Reference Laboratory for Bacterial Enteroinfections* (LRNEB) from the Oswaldo Cruz Institute (IOC/FIOCRUZ).The samples were collected through the sterilized swabs introduced carefully in the mouth, eyes, nostrils, genital slit, anus and open wounds of sick or recently dead animals. Twenty species of bacteria were detected in the animals sampled, five and 15 belonging to the family Aeromonadaceae and Vibrionaceae respectively. The most prevalent microbial species at the marine animals sampled were *Vibrio alginolyticus* and *Aeromonas caviae*, both representing 69% of detection. Green sea turtle (*Chelonia mydas*), Guiana dolphins (*Sotalia guianensis*) and Kelp gull (*Larus dominicanus*) presented 65, 45 and 35% of the 20 species of bacteria found in the analyses, respectively.

Interestingly, the three more affected species share the same habitat preferences. Both marine species are commonly observed in coastal waters of Rio de Janeiro state and prey on coastal marine food. Kelp gull are commonly found in high density consuming rest of human food at the beach, and coastal dead fishes. It is important to highlight that humans are exposed to the feces of this bird during recreation on the beach. All green sea turtles

sampled were juveniles and use coastal waters mainly to eat sea algae. Many specimens have been found sick and associated with the ingestion of marine debris [54, 55]. Guiana dolphins use coastal estuarine waters where they prey on fishes, squids and shrimps. The most important conservation problems of the species is the accidental mortality in fishing nets, but persistent pollutants seems to be also a problem for the conservation of this species [10, 56, 57]. Simultaneous occurrence of different species isolated were observed in the species sampled what could revels the possibility of synergic actions. Considering that these bacteria are recognized as emergent pathogens, and the relevance of the findings for public health in light of the growing area of "ocean and human health" we would like to emphasize the importance of this investigation, which indicates the aquatic environment as a possible route of transmission among marine biota, which includes humans. Aquatic animals are prone to bacterial infections in the same way as land animals, especially when they are under stress condition. Disease may occur systemically or be confined to external surfaces such as the skin or gills specially by pathogenic bacteria which are ubiquitous in the environment, or may form part of the normal internal bacterial flora of an aquatic animal [51].

Marine Environment and Public Health 273

outbreaks had a viral etiology, and 5 (2.6%) had a parasitic cause. Therefore it is necessary to adress appropriate studies to characterize the impact over the ocean's capacity to maintain environmental quality important to the health of marine population and the microbiological hazards present in marine ecosystems to prevent outbreaks by seafood consumption and

**WHALES DOLPHINS SEABIRDS SEA TURTLES** 

recreational use of these waters.

**BACTERIA SPECIES(BELOW)**

*A. veronii A. caviae A. hydrophila A. media A. trota* 

*V. alginolyticus V. vulnificus V. parahaemolyticus V. cincinnatiensis V. fluvialis V. furnisii V. mimicus V. harveyi V. mediterranei V. aestuarinus V. pelagius V. campbelii V. hepatarius V. coralliitycus V. fischeri* 

*Megaptera novaeangliae* 

*Eubalaena australis* 

*Balaenoptera acutorostrata* 

**Table 1.** Vibrio and Aeromonas species isolated form marine mammals, seabirds found sic on the

beaches alond the coast of Rio de Janeiro state, southeastern Brazil.

*Stenella frontalis* 

*Sotalia guianensis* 

*Pontoporia blainvillei* 

*Delphinus sp.* 

*Sula Leucogaster* 

*Larus dominicanus* 

*Spheniscus magellanicus* 

*Chelonia mydas* 

*Lepidochelys olivacea* 

*Caretta caretta* 

**BACTERIA FAMILY (BELOW)** 

**AEROMONAD**

**VIBRIONACEAE** 

**ACEA** 

In the marine ecosystem, the distribution of a viral or bacterial pathogen is directly determined by its virulence, as well as the number of susceptible hosts available. This balance between pathogen and host generates and maintains the variety of both groups. In some occasions, this delicate and normal relationship breaks, mainly due to the forces of aggression on the environment or environmental imbalances, resulting in the abundance of pathogens and increased vulnerability on marine biodiversity and public health [48]. Physical, chemical and biological marine environment may influence the number and diversity of marine microbes. However, Wang et al. [58] observed that high levels of organochlorine pollutants have been found in the tissues of Hong Kong's cetaceans, this class of chemical can cause immunosuppression, with an increased vulnerability to bacterial infections. Aquatic mammals are animals sensitive to changes in their habitat and for that reason considered excellent health indicators in environmental monitoring programs.

Ingestion of inadequately cooked seafood exposes people to parasitic infections, particularly with anisakids and cestodes, which reports increase of parasitic contamination in shellfish from polluted waters [1, 59]. In addition, many studies have shown human pathogens emerging in the marine environment and associated with infectious diseases in marine mammals exposed to polluted waters including: giardiasis, papillomavirus, brucellosis, lobomycosis, toxoplasmosis, etc.[60, 61].

Shuval [40] estimated that each year about 2.5 million clinical cases of hepatitis infections occur globally, with about 25,000 deaths and 25,000 cases of liver deficiencies associated with consumption of contaminated seafood, especially mussels. Moreover, this author estimated an overall economic impact of 7.2 billion per year associated with these conditions. Iwamoto et al. [62] showed the report to CDC during 1973 to 2006, 188 outbreaks of seafood-associated infections, causing 4,020 illnesses, 161 hospitalizations, and 11 deaths, were reported to the Food-Borne Disease Outbreak Surveillance System. Most of these seafood-associated outbreaks (n=43; 76.1%) were due to a bacterial agent; 40 (21.3%) outbreaks had a viral etiology, and 5 (2.6%) had a parasitic cause. Therefore it is necessary to adress appropriate studies to characterize the impact over the ocean's capacity to maintain environmental quality important to the health of marine population and the microbiological hazards present in marine ecosystems to prevent outbreaks by seafood consumption and recreational use of these waters.

272 Biodiversity Conservation and Utilization in a Diverse World

aquatic animal [51].

lobomycosis, toxoplasmosis, etc.[60, 61].

sampled were juveniles and use coastal waters mainly to eat sea algae. Many specimens have been found sick and associated with the ingestion of marine debris [54, 55]. Guiana dolphins use coastal estuarine waters where they prey on fishes, squids and shrimps. The most important conservation problems of the species is the accidental mortality in fishing nets, but persistent pollutants seems to be also a problem for the conservation of this species [10, 56, 57]. Simultaneous occurrence of different species isolated were observed in the species sampled what could revels the possibility of synergic actions. Considering that these bacteria are recognized as emergent pathogens, and the relevance of the findings for public health in light of the growing area of "ocean and human health" we would like to emphasize the importance of this investigation, which indicates the aquatic environment as a possible route of transmission among marine biota, which includes humans. Aquatic animals are prone to bacterial infections in the same way as land animals, especially when they are under stress condition. Disease may occur systemically or be confined to external surfaces such as the skin or gills specially by pathogenic bacteria which are ubiquitous in the environment, or may form part of the normal internal bacterial flora of an

In the marine ecosystem, the distribution of a viral or bacterial pathogen is directly determined by its virulence, as well as the number of susceptible hosts available. This balance between pathogen and host generates and maintains the variety of both groups. In some occasions, this delicate and normal relationship breaks, mainly due to the forces of aggression on the environment or environmental imbalances, resulting in the abundance of pathogens and increased vulnerability on marine biodiversity and public health [48]. Physical, chemical and biological marine environment may influence the number and diversity of marine microbes. However, Wang et al. [58] observed that high levels of organochlorine pollutants have been found in the tissues of Hong Kong's cetaceans, this class of chemical can cause immunosuppression, with an increased vulnerability to bacterial infections. Aquatic mammals are animals sensitive to changes in their habitat and for that reason considered excellent health indicators in environmental monitoring programs.

Ingestion of inadequately cooked seafood exposes people to parasitic infections, particularly with anisakids and cestodes, which reports increase of parasitic contamination in shellfish from polluted waters [1, 59]. In addition, many studies have shown human pathogens emerging in the marine environment and associated with infectious diseases in marine mammals exposed to polluted waters including: giardiasis, papillomavirus, brucellosis,

Shuval [40] estimated that each year about 2.5 million clinical cases of hepatitis infections occur globally, with about 25,000 deaths and 25,000 cases of liver deficiencies associated with consumption of contaminated seafood, especially mussels. Moreover, this author estimated an overall economic impact of 7.2 billion per year associated with these conditions. Iwamoto et al. [62] showed the report to CDC during 1973 to 2006, 188 outbreaks of seafood-associated infections, causing 4,020 illnesses, 161 hospitalizations, and 11 deaths, were reported to the Food-Borne Disease Outbreak Surveillance System. Most of these seafood-associated outbreaks (n=43; 76.1%) were due to a bacterial agent; 40 (21.3%)

**Table 1.** Vibrio and Aeromonas species isolated form marine mammals, seabirds found sic on the beaches alond the coast of Rio de Janeiro state, southeastern Brazil.

#### **6. Bioinvasion in coastal systems**

The bioinvasion, refers to some exotic species introduced into a new environment, and which for the absence of natural controls such as parasites and diseases, become extremely harmful to local biodiversity, especially in disturbed habitats [11, 63]. When a species introduced into a new environment has success in establishing itself and its population increases, it tends to compete and eliminate native species, or cause damage to local ecology and affect socio-economic pattern and public health [45]. The bioinvasion is considered one of the most important threats to biodiversity and integrity of marine ecosystems, especially in coastal regions. However, this question had deserved attention only after the signing of the Convention on Biological Diversity in June 1992. Bioinvasions have occurred in all regions of the world, and the largest carrier of exotic species to new areas is navigation, where the ballast water of ships acting as a "vector" for introduction of species [63].

Marine Environment and Public Health 275

Approximately 80% of the contamination that reaches the oceans has their emission sources on the continents, via air routes, direct discharges into the oceans by effluents, industrial, agricultural and other sources [68]. The ocean contamination in associated with the concentration of people living in coastal regions around the world [18]. The contaminants of highest concern are those that have environmental persistence, are capable of long-range transport, can biomagnify in food chain and bioaccumulate in humans and animal tissues and have potentially significant impacts on humans and environmental health [66, 69-71]. The sources and amount of emissions are also extremely important. Persistent organic pollutants (POPs), polycyclic aromatic hydrocarbons (PAHs) and some metals present the

The human activities have considerably altered the geochemical and biogeochemical cycles of the metals in nature, especially during the last and current century. Once the environment, the metallic elements can occur in various chemical forms and thus may increase or decrease its toxic properties [1, 72]. Mercury, which has been associated with various human health problems, is used in wide range of industrial processes. When released into the environment, bacteria can quickly transform its inorganic form in inorganic mercury (methyl-mercury). Methyl-mercury can concentrate in the marine food chain, and may cause cytotoxic effects, kidney and brain of those exposed [10, 57, 72]. Concentrations 1- 2 mg / kg brain tissue may cause neurological damage. Furthermore, due to its ability to cross the placental barrier, methyl-mercury becomes extremely harmful to fetuses exposed [1]. Due to the extensive contamination with mercury, individuals consuming fish (principally predator species) frequently exhibit the highest levels of methyl-mercury in their tissues. Top predator species such as marine mammals, sharks and seabirds present extremely high concentrations or mercury in their tissues, and people that consume meat of

The human vulnerability for persistent contaminants in the ocean is strongly linked to the origin and trophic position of the marine food consumed. An example of this is people in Iraq and Japan, which may have higher levels of 50-100 ppm of methyl-mercury in hair samples, when the average concentration of this compound in humans is less than 1 ppm [73]. Cadmium also has the ability to bioaccumulate in the marine environment and is often found in biological samples taken from this environment. Cadmium is recognized as a human carcinogen; however, the increased risk is related to human exposure to this element

Arsenic and lead are also potentially harmful to human and environmental health. These are usually found in living organisms and marine sediments, industrial discharges being a major source of environmental emissions. Several related contaminants have been found in tissues of marine organisms, and in some cases these have been associated with adverse effects on the exposed organisms [3]. One of the variables which can cause confusion and lack of causal association studies is the presence of mixtures of a considerable range of these specific contaminants present in the oceans. This mixture could cause adverse effects acting in concert, and perhaps at low levels, which could obscure associations in studies using only

organisms from these groups generally are exposed to high concentrations.

chemical characteristics mentioned above.

can lead to proteinuria and renal failure.

specific contaminants.

Climate change, nitrogen deposition and contaminants in the marine environment appear to help the successful accommodation of invasive species in a new habitat, especially microorganisms [11, 64]. Several marine species have caused heavy economic and ecologic impacts in a habitat invaded. Once established, the elimination of exotic species in the new habitat is very costly or even impossible, therefore, the policies related to bioinvasion have been linked to measures to prevent introduction of exotic species [65]. The exchange of ballast water of ships in coastal areas of a new marine ecosystem is considered the main introduction factor for alien species [11, 63]. One of the main problems of bioinvasion related to public health is the introduction of toxic algae that cause poisoning and other pathogens such as *Vibrio cholerae*, which causes of infection [13, 63, 64].

In 1991, cholera appeared in Latin America, and until recently caused more than 1.2 million of infections and 12,000 deaths. It is believed that Peru served as an entry in the South American continent [63]. However, Brazil has achieved the highest number of cases across the continent in 1993 and 1994, most recently in 1999 on the coast of Paraná, with 467 confirmed cases [13]. There is scientific evidence showing that the first cases of cholera occurred in the coastal ports, which suggests that outbreaks or epidemics could have been caused by the ballast water of ships arriving from endemic areas [63]. In a study conducted by the National Health Surveillance Agency (ANVISA) in 2002 detected the presence of *Vibrio cholerae* and *Escherichia coli* in high proportions in samples collected from ballast water of ships in various ports of Brazil, supporting the hypothesis of ships as carriers of the pathogen [13].

#### **7. Environmental contaminants**

Chemical contamination is one of the main challenges for the conservation status of the marine environment. Environmental contaminants have compromised the quality of water and air, affecting biodiversity in ecosystems, contaminating food and endangering human health. The vast majority of waste produced by anthropogenic activities inevitably reaches the oceans and is widely dispersed and may even reach free regions of the release of pollutants, such as the Antarctic region [3, 5, 12, 66, 67].

Approximately 80% of the contamination that reaches the oceans has their emission sources on the continents, via air routes, direct discharges into the oceans by effluents, industrial, agricultural and other sources [68]. The ocean contamination in associated with the concentration of people living in coastal regions around the world [18]. The contaminants of highest concern are those that have environmental persistence, are capable of long-range transport, can biomagnify in food chain and bioaccumulate in humans and animal tissues and have potentially significant impacts on humans and environmental health [66, 69-71]. The sources and amount of emissions are also extremely important. Persistent organic pollutants (POPs), polycyclic aromatic hydrocarbons (PAHs) and some metals present the chemical characteristics mentioned above.

274 Biodiversity Conservation and Utilization in a Diverse World

The bioinvasion, refers to some exotic species introduced into a new environment, and which for the absence of natural controls such as parasites and diseases, become extremely harmful to local biodiversity, especially in disturbed habitats [11, 63]. When a species introduced into a new environment has success in establishing itself and its population increases, it tends to compete and eliminate native species, or cause damage to local ecology and affect socio-economic pattern and public health [45]. The bioinvasion is considered one of the most important threats to biodiversity and integrity of marine ecosystems, especially in coastal regions. However, this question had deserved attention only after the signing of the Convention on Biological Diversity in June 1992. Bioinvasions have occurred in all regions of the world, and the largest carrier of exotic species to new areas is navigation,

where the ballast water of ships acting as a "vector" for introduction of species [63].

pathogens such as *Vibrio cholerae*, which causes of infection [13, 63, 64].

Climate change, nitrogen deposition and contaminants in the marine environment appear to help the successful accommodation of invasive species in a new habitat, especially microorganisms [11, 64]. Several marine species have caused heavy economic and ecologic impacts in a habitat invaded. Once established, the elimination of exotic species in the new habitat is very costly or even impossible, therefore, the policies related to bioinvasion have been linked to measures to prevent introduction of exotic species [65]. The exchange of ballast water of ships in coastal areas of a new marine ecosystem is considered the main introduction factor for alien species [11, 63]. One of the main problems of bioinvasion related to public health is the introduction of toxic algae that cause poisoning and other

In 1991, cholera appeared in Latin America, and until recently caused more than 1.2 million of infections and 12,000 deaths. It is believed that Peru served as an entry in the South American continent [63]. However, Brazil has achieved the highest number of cases across the continent in 1993 and 1994, most recently in 1999 on the coast of Paraná, with 467 confirmed cases [13]. There is scientific evidence showing that the first cases of cholera occurred in the coastal ports, which suggests that outbreaks or epidemics could have been caused by the ballast water of ships arriving from endemic areas [63]. In a study conducted by the National Health Surveillance Agency (ANVISA) in 2002 detected the presence of *Vibrio cholerae* and *Escherichia coli* in high proportions in samples collected from ballast water of ships in various ports of Brazil, supporting the hypothesis of ships as carriers of the

Chemical contamination is one of the main challenges for the conservation status of the marine environment. Environmental contaminants have compromised the quality of water and air, affecting biodiversity in ecosystems, contaminating food and endangering human health. The vast majority of waste produced by anthropogenic activities inevitably reaches the oceans and is widely dispersed and may even reach free regions of the release of

**6. Bioinvasion in coastal systems** 

pathogen [13].

**7. Environmental contaminants** 

pollutants, such as the Antarctic region [3, 5, 12, 66, 67].

The human activities have considerably altered the geochemical and biogeochemical cycles of the metals in nature, especially during the last and current century. Once the environment, the metallic elements can occur in various chemical forms and thus may increase or decrease its toxic properties [1, 72]. Mercury, which has been associated with various human health problems, is used in wide range of industrial processes. When released into the environment, bacteria can quickly transform its inorganic form in inorganic mercury (methyl-mercury). Methyl-mercury can concentrate in the marine food chain, and may cause cytotoxic effects, kidney and brain of those exposed [10, 57, 72]. Concentrations 1- 2 mg / kg brain tissue may cause neurological damage. Furthermore, due to its ability to cross the placental barrier, methyl-mercury becomes extremely harmful to fetuses exposed [1]. Due to the extensive contamination with mercury, individuals consuming fish (principally predator species) frequently exhibit the highest levels of methyl-mercury in their tissues. Top predator species such as marine mammals, sharks and seabirds present extremely high concentrations or mercury in their tissues, and people that consume meat of organisms from these groups generally are exposed to high concentrations.

The human vulnerability for persistent contaminants in the ocean is strongly linked to the origin and trophic position of the marine food consumed. An example of this is people in Iraq and Japan, which may have higher levels of 50-100 ppm of methyl-mercury in hair samples, when the average concentration of this compound in humans is less than 1 ppm [73]. Cadmium also has the ability to bioaccumulate in the marine environment and is often found in biological samples taken from this environment. Cadmium is recognized as a human carcinogen; however, the increased risk is related to human exposure to this element can lead to proteinuria and renal failure.

Arsenic and lead are also potentially harmful to human and environmental health. These are usually found in living organisms and marine sediments, industrial discharges being a major source of environmental emissions. Several related contaminants have been found in tissues of marine organisms, and in some cases these have been associated with adverse effects on the exposed organisms [3]. One of the variables which can cause confusion and lack of causal association studies is the presence of mixtures of a considerable range of these specific contaminants present in the oceans. This mixture could cause adverse effects acting in concert, and perhaps at low levels, which could obscure associations in studies using only specific contaminants.

Persistent organic pollutants (POPs) pose potential risks to human health and the environment. Exposure to POPs can cause serious human and environmental health impacts including certain cancers, birth defects, dysfunctional immune and reproductive systems and greater susceptibility to disease [1, 70].

Marine Environment and Public Health 277

Great efforts have been made to evaluate the complex economic values of environmental services and natural resources. Generally, the conservation of the ecosystem is considered more economically profitable than the economic values arising from the acquisition and use of its resources, which often leave severe environmental liabilities [30, 77]. Constanza et al. [77] showed that while the coastal areas cover only 8% of global land surface, the services and benefits from this area are responsible for approximately 43% of the total value of global

In the last six decades there has been a growing interest in bioactive substances with properties derived from marine organisms [1, 4, 16, 78]. Already in the 1950s Bergman and Feeney [79] discovered two drugs of importance to medicine (ARA-C and ARA-A), based on nucleoside present in marine sponges (*Tectitethya crypta* and *Streptomyces antibiotics*). Formulated synthetically from the discovery of these researchers, the Ara-C is indicated for the treatment of non-lymphocytic leukemia, the leukemia meninges and chronic myelocytic leukemia, whereas the Ara-A is indicated for the treatment of viral infections caused by *Herpes simplex* and *Herpes zoster* [4, 43, 80]. Another valuable contribution of importance to medicine was the discovery of azidothymidine, AZT. This synthetic derivative, originating from marine sponges, is currently still one of the most effective drugs in the treatment of acquired immunodeficiency syndrome (AIDS) [43, 80]. From the work of these researchers, scientists began to explore marine biodiversity and its potential for the discovery of new bioactive compounds, aimed at advancement of pharmacology and biomedicine in the treatment of diseases known to cause severe damage on the population. The success of the discovery of new bioactive compounds and their pharmacological effects, extracted from marine organisms has been demonstrated from formulations of new anticancer treatments, and infectious diseases and inflammation [81]. However, much emphasis has been attributed to the discovery of anti-cancer compounds derived from marine organisms due in large part to the availability of funds for supporting studies aiming to find new compounds. The oceans are rich source of chemical and biological diversity, with hundreds of thousands, maybe even millions of new species are still unknown, especially micro-organisms that represent a great opportunity for the discovery of new species and new chemicals. Another approach of extreme importance is the study of marine organisms as a basis for discovery in biomedicine. Research on the natural history, taxonomy, physiology and biochemistry of marine organisms has served as a model for biomedical research to elucidate issues relevant

The pressure of human activities on marine environment generates ecosystem modifications that affect the people depending on the vulnerability of the population exposed. The past and current human development needs great modification to ensure the stabilization and homeostasis of the ocean. In addition, it is important to better understand the dynamic of the marine processes which can contribute to prevent the risks associated with human exposure. It includes the development of a system capable to generate information of a wide range of complex environment processes that should be used to prevent human and

ecosystem services valued at 12.6 trillion dollars.

to the physiology, biochemistry and human disease.

**9. Conclusions** 

The main human exposure to POPs in the oceans is through fish consumption [74]. One of the most relevant POPs even today is the pesticide DDT, which despite its commercialization and application banned in most countries, is still used in some tropical and subtropical nations for vector control, such as malaria [69, 75, 76]. According to the International Agency for Research on Cancer (IARC), DDT is possibly carcinogenic and sub-acute exposures may cause problems in the central nervous system and also impair the immunological integrity. Similarly, PCBs (polychlorinated biphenyls) have caused severe impacts on the exposed organisms and public health, mainly through fish consumption [74].

PAHs are pollutants of great environmental persistence, and together with its derivatives have important carcinogenic, mutagenic and genotoxic [71]. PAHs are formed by thermal transformation of fossil fuels. Thus, forest fires, industrial processes and petrochemical activities are major contributors to environmental contamination by PAHs [1, 71]. These can also be formed naturally, but anthropogenic is that is causing concern. PAHs are highly soluble and rapidly absorbed through the lungs, the intestines and the skin of experimental animals, regardless of route of administration. The carcinogenic effects of some PAHs Of crucial importance to environmental and public health, fish consumption is the main source of human exposure relating to ocean pollution.
