**2. Antibiotics real state consummation and biodegradability**

Tons of pharmaceutical antibiotics have been produced by the industry. The worldwide production of antibiotics is estimated to be in the order of 100.000 tons per year [17], and 73% in the world and 80% in the United States is used for livestock consummation [18]. Different from the European Union, where the amount of antibiotic used is 60% for humans and 40% for animals and crops [19]. The great threat as warned by the WHO is to increase the resistance to antibiotics not only by pathogens but also by environmental organisms, which can lead to possible environmental damage (https://www.who.int/news/item/07-11-2017-stop-usingantibiotics-in-healthy-animals-to-prevent-the-spread-of-antibiotic-resistance). Now WHO is recommending avoiding the use of antibiotics in healthy animals.

Antibiotics were approved in the USA in the next order: sulfonamides in 1935, penicillin in 1941, aminoglycosides in 1944, cephalosporins in 1945, chloramphenicol in 1949, tetracyclines in 1950, macrolides/lincosamides/streptogramins in 1952, glycopeptides in 1956, rifamycins in 1957, nitroimidazoles in 1959, quinolones in 1962, trimethoprim in 1968, oxazolidinones in 2000, lipopeptides in 2003 [20]. **Table 1** relates the antibiotics with their molecular functional group and in the last column their resistance model in microorganisms. Another problem is that antibiotics are not used alone and come with stimulators and enhancers, such as clavulanic acid which helps overcome β-lactam resistance.


*Emerging Contaminants*

livestock, poultry, swine, and crop industries [6–9]. However, pharmaceutical antibiotics at a significant level in nature and different environments has been detected in previous studies and monitoring in plains, valleys, coast, and mountains, when were monitored in hospital wastewater, farms, rivers, and coastal water [10–13]. Antibiotics emerge as new environment contaminants as plastics, pesticides, among others. The main risk and concern as the pesticides are microbial antibiotics and multidrug resistance. The human being is developing littles Frankenstein, likely by carelessness and naivety, contrary to genetically modified organisms (GMOs) opinion, the scare of gene manipulation, and its ethical reflection by the Scientifics and public [14, 15]. The consumer has scary to GMOs, but without laboratory use, the human being is making GMOs resistant to antibiotics. The controversy is rising, why the public is concerned by artificial experiments but carefree by antibiotics pollutants? This environmental risk goes in the same way as global warming.

Probably some natural antibiotic-resistant bacteria in soil gain multidrug resistance consequence by human practices as livestock or water activities. However, antibiotics come to the soil by wastewater from human or animal feces together with the selection of antibiotic-resistant microbiome [16]. Antibiotics and bacteria remain in the soil until water carries them to stream or rivers or are transferred by

**Water carries on antibiotics.** *Water from hospitals and farms could pass through sewage treatment, but in many countries, those health and environmental rules are not applied or respected, especially in developing countries by poor investment and low budget. Water is used for human consummation, livestock, poultry, swine, and soil irrigation to crop grass and agriculture plants. But lockdown animals, cattle, and others get sick and must be under antibiotic treatment. Then, this sanitary water passes directly to the sewer rarely treated and directly deposed in the streams and rivers. Antibiotics are used in some countries to yield more muscular biomass of livestock, poultry, and swine. This practice increases the level of antibiotics in soil, humans, flora, and fauna. Likely, some soils intersperse antibiotics in roots, stems, leaves, and fruits for human consummation. Even, antibiotics in the soil are absorbed by bacteria, fungi, protists, and invertebrates. Soils stock, pick up, and pour antibiotics in streams, then to rivers and finally to the sea. The pharmaceutical antibiotics were poured into the sea for 70 years. Surely the antibiotics levels in nature and water were not the same before the pharmaceutical antibiotic' revolution and production. This image is an actual case in South America, where some hospitals lack the budget to invest in the sewage treatment plant. Near this real example, there are other little villages where its hospital has two water treatment plants, one for human consummation and the other for sewage. In that case, contaminated hospital water never goes back to flow, however, many farms invest weakly in the water treatment* 

*process, ejecting polluted water to the environment with antibiotics and pesticides.*

**164**

**Figure 1.**


**167**

**Table 1.**

*Biodegradability and resistance***.**

*Pharmaceutical Antibiotics at a Significant Level in Nature: From Hospitals, Livestock…*

**Class Example(s) Functional group or whole molecule Model(s) of** 

**Sulfonamides** Sulfamethoxazole Efflux, altered

**Rifamycins** Rifampin ADP-ribosylation,

**Lipopeptides** Daptomycin Altered target

**Cationic** Colistin Altered target,

**Nystatin** Mycostatin Ergosterol pathway

*The most used pharmaceutical antibiotics, showing class, examples, functional group or whole molecule and models of resistance. Base on from the Gartiser et al. [21], Davies and Davies [22], Li & Zhang [23] and Zhi et al. [24].*

**resistance**

efflux, altered target

target

efflux

Efflux

Currently, animal production practices are linked with the routine use of antibiotics, and the selection pressure on bacteria is increasing the potential resistance [18]. For example, at the United States, the antibiotics use is broadly applied for animals and crops. This has been a controversial topic for over 30 years. A 1998 report from the prestigious Institute of Medicine of the National Academy of Sciences noted that about 4 million pounds (2000 tons) of antibiotics were used to treat sick farm animals and another 16 million pounds (8000 tons) were used as growth promotions (low doses of antibiotics usually included in animal feed) for animals every year [3]. Worldwide, in 2010, livestock consumed at least 63,200 tons

Many investigations pointed out to de biodegradation of antibiotics, but some

ones are biodegradable and other ones are accumulative in soil and water [21, 23, 24]. However, this concern is poorly studied today, for example

of antibiotics, more than all human consumption [18].

Erythromycin, nystatin and sulfomethoxazole,

*DOI: http://dx.doi.org/10.5772/intechopen.95368*


*Pharmaceutical Antibiotics at a Significant Level in Nature: From Hospitals, Livestock… DOI: http://dx.doi.org/10.5772/intechopen.95368*

*The most used pharmaceutical antibiotics, showing class, examples, functional group or whole molecule and models of resistance. Base on from the Gartiser et al. [21], Davies and Davies [22], Li & Zhang [23] and Zhi et al. [24].*

#### **Table 1.**

*Emerging Contaminants*

**Tetracyclines** Minocycline,

**Macrolides** Erythromycin,

tigecycline

azithromicin

**Class Example(s) Functional group or whole molecule Model(s) of** 

**Lincosamides** Clindamycin Nucleotidylation,

**Streptogramins** Synercid C-O lyase (type B

**Oxazolidinones** Linezolid Efflux, altered

**Phenicols** Chloramphenicol Acetylation, efflux,

**Quinolones** Ciprofloxacin Acetylation, efflux,

**Pyrimidines** Trimethoprim Efflux, altered

**resistance**

Hydrolysis, glycosylation, phosphorylation, efflux, altered target

efflux, altered target

streptogramins), acetylation (type A streptogramins), efflux, altered target

target

altered target

altered target

target

Monooxygenation, efflux, altered target

**166**

*Biodegradability and resistance***.**

Currently, animal production practices are linked with the routine use of antibiotics, and the selection pressure on bacteria is increasing the potential resistance [18]. For example, at the United States, the antibiotics use is broadly applied for animals and crops. This has been a controversial topic for over 30 years. A 1998 report from the prestigious Institute of Medicine of the National Academy of Sciences noted that about 4 million pounds (2000 tons) of antibiotics were used to treat sick farm animals and another 16 million pounds (8000 tons) were used as growth promotions (low doses of antibiotics usually included in animal feed) for animals every year [3]. Worldwide, in 2010, livestock consumed at least 63,200 tons of antibiotics, more than all human consumption [18].

Many investigations pointed out to de biodegradation of antibiotics, but some ones are biodegradable and other ones are accumulative in soil and water [21, 23, 24]. However, this concern is poorly studied today, for example Erythromycin, nystatin and sulfomethoxazole,

#### **Figure 2.**

**Level of some antibiotic's detection***. The detection level of certain antibiotics in ng/L evaluated in soil by [19] work. The data from [29] report is not diagrammed, only penicillin and macrolides were in the highest concentration for the detection, which would leave [19]'s data almost at baseline.*
