**6. Antibiotics in drinking water, farm water, and aquifers**

Perhaps one of the most worrisome issues with non-treatment of hospital water is that water with antibiotics can reach farms and/or water for human or animal consumption and even plant irrigation. In Kumasi, a big city in Ghana, the hospital wastewater and effluents from waste stabilization ponds, are directly discharged as low-quality water into nearby streams which are eventually used to irrigate vegetables. The presence of 12 commonly used antibiotics was detected: metronidazole, ciprofloxacin, erythromycin, trimethoprim, ampicillin, cefuroxime, sulfamethoxazole, amoxicillin, tetracycline, oxytetracycline, chlortetracycline,

and doxycycline [44]. The authors reported 15 μg/L for ciprofloxacin in hospital wastewater, and after the antibiotic concentration in irrigation water was up from 0.2 μg/L to 200 ng/L; these quantities lead us to think or almost elucubrating a refined method to purify and reuse those antibiotic as the recycling urine to purify drink water at International Station at the space. Seriously, we imagine that astronauts did not consume antibiotics before (https://asgardia.space/en/news/Drugsin-Space-What-Can-Get-an-Astronaut-High) [45]. Peculiar because everybody on the Earth consumes antibiotics without prescription, for instance in one preschool in Hong Kong, 31 children were detected veterinary antibiotics in urine, not human antibiotics. Norfloxacin and penicillin were the main antibiotics detected (48.4% and 35.5%, respectively), with median concentrations of 0.037 and 0.13 ng/mL, respectively [46]. In the same study enrofloxacin, penicillin, and erythromycin were the most detected veterinary antibiotics in raw and cooked food.

In many countries, farm irrigation water is already a vehicle for various antibiotics causing bioaccumulation in crop plants such as tomatoes and wheat crops [25, 47]. However, the bioaccumulation of antibiotics on tomatoes irrigated with wastewater is no consistent and depends on the high concentration of antibiotics on soil [25]. But researches reveal that hazardous quotidian (HQ ) values show that the consumption of fruits harvested from tomato plants irrigated for long period with the wastewater applied for irrigation under field conditions in this study represents a low risk to human health [25]. On the other hand, in wheat plants that were spray-irrigated with wastewater treatment plant effluent, ofloxacin was found throughout the plant, with higher concentrations in the straw (10.2 ± 7.05 ng/g) and lower concentrations in the grain (2.28 ± 0.89 ng/g). Trimethoprim was found only on grain or straw surfaces, whereas carbamazepine and sulfamethoxazole were concentrated within the grain (1.88 ± 2.11 and 0.64 ± 0.37 ng/g, respectively). These findings demonstrate that pharmaceuticals and personal care products (PPCPs) can be taken up into wheat plants and adhere to plant surfaces when WWTP effluent is spray-irrigated [47].

Identical to what happened with pesticides, cyanide, and mercury, one of the biggest pollution problems today is that of aquifers. Wang et al. [48] evaluated the presence of antibiotics in groundwater up to 50 meters of aquifers, finding seasonal differences in spring, summer, and winter an average value of 1.60 μg/L, 0.772 μg/L, and 0.546 μg/L respectively. The predominant antibiotics were fluoroquinolones and tetracyclines, but the highest risk probably will be erythromycin for algae in surface waters and in deep waters, where ciprofloxacin would be the most concentrated among the 14 antibiotics.

#### **7. Antibiotics in agricultural practices in farms**

A disturbing issue today in farms and ranches as industry type is that in these places the handling of antibiotics is on a large scale even in higher quantities than in hospitals. There is overestimation since we mention before that in the United States the 80% of antibiotics are used for livestock consummation [18], which must be very similar in many countries in which these levels are allowed, or where there is not even a single rule about it. We previously mentioned the irrigation of tomato and wheat with water contaminated with antibiotics [25, 47], that is, in an indirect relationship to antibiotic management. We will now talk about the direct handling of antibiotics by the farms and what consequences this has brought to their soil and water. No, the issue is another, for example, many farms have their aqueducts or crop irrigation systems. There are very few studies on pesticide and antibiotic composition, and except for supported studies, where health and environment are the

**171**

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

concerns and priority. From those studies is possible to collect valuable information. It is important to emphasize that some veterinary antibiotics have been handled as dietary supplements or as a supplement for spraying crops. This is the case of Chung et al. [49], who investigates veterinary antibiotics in soil experimentally contaminated by chlortetracycline, enrofloxacin, and sulphathiazole and translocated and bioaccumulates in roots and leaves of radish. They established that the concentration of chlortetracycline was lower than 2.73%, for enrofloxacin ranged 0.08–3.90%, and sulphathiazole lower than 1.64%. In another study in north China [50], the authors look at antibiotics in manure, soil, vegetables, and groundwater. This interesting work mentioned the complex antibiotic translocation from manure to the soil, establishing residual rate (RR) of antibiotics (mg/kg ha yr). The antibiotics used were sulfamethoxazole (SMZ), sulfadoxine (SDO), sulfachlorpyridazine (SCP) and chloramphenicol (CAP), oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC), lincomycin (LIN), ofloxacin (OFL), ciprofloxacin (CIP). They conclude that with the application of manure containing antibiotics to organic vegetable bases, the residues of antibiotics in soil, vegetables, and groundwater were widely detected, mainly OTC, TC, CTC, and SCP with RR from 1,6 to 43% and the range of antibiotics in vegetable was 0.1-532 mg/kg using radish, rape, celery, coriander, which not all antibiotics were detectable. An interesting large study in northeastern China [51] using feces from chicken, pig, and dairy cow, 14 veterinary antibiotics such as tetracycline, oxytetracycline, chlortetracycline, ciprofloxacin, sulfaguanidine (SG), sulfanilamide(SA), sulfamethoxazole, sulfamonomethoxine (SMM), sulfamerazine (SMR), sulfachlorpyridazine (SCP), norfloxacin (NOR), enrofloxacin (ENR), difloxacin (DIF), and tylosin (TYL) were detected by HPLC, which six antibiotics (OTC, CTC, TC, TYL, SCP, and SMZ) were assessed using the hazard quotient (HQ ). The 14 veterinary antibiotics detected in three types of animal feces the authors found that antibiotics occurred 7,41 to 57,41% inside 54 samples, and the levels ranged from 0,08 to 56.81 mg/kg. TCs were predominant with a maximum level of 56.81 mg/kg mostly detected in pig feces. SAs were common and detected with the highest concentration of 7.11 mg/kg. Fluoroquinolones were more widely detected in chicken feces rather than in pig or dairy cow manure,

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

which contained the dominant antibiotic ENR [51].

bacteria related to environmental contamination.

Other interesting studies in Waseca and Staples, Minnesota USA, used chlortetracycline, monensin, sulfamethazine, tylosin, and virginiamycin evaluated in 11 vegetable crops in two different soils fertilized with raw versus composted turkey and hog manure or inorganic fertilizer [52], the authors conclude that all antibiotics in vegetable tissues were generally less than the limits of quantification were less than 10 μg/kg, and radish peel and spinach leaf were the vegetables that bioaccumulated more antibiotics than others ranging from 4 to 6 μg/kg. In other research, the authors evaluated the transfer of five different antibiotics such as tetracycline, sulfamethazine, norfloxacin, erythromycin, and chloramphenicol (CAP) evaluated in carrot, tomato, and lettuce under two levels of antibiotic-contaminated wastewater irrigation and animal manure fertilization [53]. TC, NOR, and CAP were accumulated at higher levels in the shoots/leaves than the other two compounds, except for CAP in carrot. Likewise, this work concludes that the levels of antibiotics are in acceptable daily intake (ADI), indicating that the main problem is not bioaccumulation in plants or animals, but bioaccumulation in multi-drug resistant

As it was previously mentioned, Sulfonamides (SAs) are one of the most persistent antibiotics in soil and water, but especially bioaccumulate, and more than three tons of SM are used annually in Europe for swine production [54]. Li et al. [54] evaluated SAs in pakchoi cabbage such as sulfadiazine (SDZ), sulfamethazine (SM2), and SMZ. The three antibiotics are spiked in soil could be taken up by

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

concerns and priority. From those studies is possible to collect valuable information. It is important to emphasize that some veterinary antibiotics have been handled as dietary supplements or as a supplement for spraying crops. This is the case of Chung et al. [49], who investigates veterinary antibiotics in soil experimentally contaminated by chlortetracycline, enrofloxacin, and sulphathiazole and translocated and bioaccumulates in roots and leaves of radish. They established that the concentration of chlortetracycline was lower than 2.73%, for enrofloxacin ranged 0.08–3.90%, and sulphathiazole lower than 1.64%. In another study in north China [50], the authors look at antibiotics in manure, soil, vegetables, and groundwater. This interesting work mentioned the complex antibiotic translocation from manure to the soil, establishing residual rate (RR) of antibiotics (mg/kg ha yr). The antibiotics used were sulfamethoxazole (SMZ), sulfadoxine (SDO), sulfachlorpyridazine (SCP) and chloramphenicol (CAP), oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC), lincomycin (LIN), ofloxacin (OFL), ciprofloxacin (CIP). They conclude that with the application of manure containing antibiotics to organic vegetable bases, the residues of antibiotics in soil, vegetables, and groundwater were widely detected, mainly OTC, TC, CTC, and SCP with RR from 1,6 to 43% and the range of antibiotics in vegetable was 0.1-532 mg/kg using radish, rape, celery, coriander, which not all antibiotics were detectable. An interesting large study in northeastern China [51] using feces from chicken, pig, and dairy cow, 14 veterinary antibiotics such as tetracycline, oxytetracycline, chlortetracycline, ciprofloxacin, sulfaguanidine (SG), sulfanilamide(SA), sulfamethoxazole, sulfamonomethoxine (SMM), sulfamerazine (SMR), sulfachlorpyridazine (SCP), norfloxacin (NOR), enrofloxacin (ENR), difloxacin (DIF), and tylosin (TYL) were detected by HPLC, which six antibiotics (OTC, CTC, TC, TYL, SCP, and SMZ) were assessed using the hazard quotient (HQ ). The 14 veterinary antibiotics detected in three types of animal feces the authors found that antibiotics occurred 7,41 to 57,41% inside 54 samples, and the levels ranged from 0,08 to 56.81 mg/kg. TCs were predominant with a maximum level of 56.81 mg/kg mostly detected in pig feces. SAs were common and detected with the highest concentration of 7.11 mg/kg. Fluoroquinolones were more widely detected in chicken feces rather than in pig or dairy cow manure, which contained the dominant antibiotic ENR [51].

Other interesting studies in Waseca and Staples, Minnesota USA, used chlortetracycline, monensin, sulfamethazine, tylosin, and virginiamycin evaluated in 11 vegetable crops in two different soils fertilized with raw versus composted turkey and hog manure or inorganic fertilizer [52], the authors conclude that all antibiotics in vegetable tissues were generally less than the limits of quantification were less than 10 μg/kg, and radish peel and spinach leaf were the vegetables that bioaccumulated more antibiotics than others ranging from 4 to 6 μg/kg. In other research, the authors evaluated the transfer of five different antibiotics such as tetracycline, sulfamethazine, norfloxacin, erythromycin, and chloramphenicol (CAP) evaluated in carrot, tomato, and lettuce under two levels of antibiotic-contaminated wastewater irrigation and animal manure fertilization [53]. TC, NOR, and CAP were accumulated at higher levels in the shoots/leaves than the other two compounds, except for CAP in carrot. Likewise, this work concludes that the levels of antibiotics are in acceptable daily intake (ADI), indicating that the main problem is not bioaccumulation in plants or animals, but bioaccumulation in multi-drug resistant bacteria related to environmental contamination.

As it was previously mentioned, Sulfonamides (SAs) are one of the most persistent antibiotics in soil and water, but especially bioaccumulate, and more than three tons of SM are used annually in Europe for swine production [54]. Li et al. [54] evaluated SAs in pakchoi cabbage such as sulfadiazine (SDZ), sulfamethazine (SM2), and SMZ. The three antibiotics are spiked in soil could be taken up by

*Emerging Contaminants*

spray-irrigated [47].

concentrated among the 14 antibiotics.

**7. Antibiotics in agricultural practices in farms**

and doxycycline [44]. The authors reported 15 μg/L for ciprofloxacin in hospital wastewater, and after the antibiotic concentration in irrigation water was up from 0.2 μg/L to 200 ng/L; these quantities lead us to think or almost elucubrating a refined method to purify and reuse those antibiotic as the recycling urine to purify drink water at International Station at the space. Seriously, we imagine that astronauts did not consume antibiotics before (https://asgardia.space/en/news/Drugsin-Space-What-Can-Get-an-Astronaut-High) [45]. Peculiar because everybody on the Earth consumes antibiotics without prescription, for instance in one preschool in Hong Kong, 31 children were detected veterinary antibiotics in urine, not human antibiotics. Norfloxacin and penicillin were the main antibiotics detected (48.4% and 35.5%, respectively), with median concentrations of 0.037 and 0.13 ng/mL, respectively [46]. In the same study enrofloxacin, penicillin, and erythromycin

were the most detected veterinary antibiotics in raw and cooked food.

In many countries, farm irrigation water is already a vehicle for various antibiotics causing bioaccumulation in crop plants such as tomatoes and wheat crops [25, 47]. However, the bioaccumulation of antibiotics on tomatoes irrigated with wastewater is no consistent and depends on the high concentration of antibiotics on soil [25]. But researches reveal that hazardous quotidian (HQ ) values show that the consumption of fruits harvested from tomato plants irrigated for long period with the wastewater applied for irrigation under field conditions in this study represents a low risk to human health [25]. On the other hand, in wheat plants that were spray-irrigated with wastewater treatment plant effluent, ofloxacin was found throughout the plant, with higher concentrations in the straw (10.2 ± 7.05 ng/g) and lower concentrations in the grain (2.28 ± 0.89 ng/g). Trimethoprim was found only on grain or straw surfaces, whereas carbamazepine and sulfamethoxazole were concentrated within the grain (1.88 ± 2.11 and 0.64 ± 0.37 ng/g, respectively). These findings demonstrate that pharmaceuticals and personal care products (PPCPs) can be taken up into wheat plants and adhere to plant surfaces when WWTP effluent is

Identical to what happened with pesticides, cyanide, and mercury, one of the biggest pollution problems today is that of aquifers. Wang et al. [48] evaluated the presence of antibiotics in groundwater up to 50 meters of aquifers, finding seasonal differences in spring, summer, and winter an average value of 1.60 μg/L, 0.772 μg/L, and 0.546 μg/L respectively. The predominant antibiotics were fluoroquinolones and tetracyclines, but the highest risk probably will be erythromycin for algae in surface waters and in deep waters, where ciprofloxacin would be the most

A disturbing issue today in farms and ranches as industry type is that in these places the handling of antibiotics is on a large scale even in higher quantities than in hospitals. There is overestimation since we mention before that in the United States the 80% of antibiotics are used for livestock consummation [18], which must be very similar in many countries in which these levels are allowed, or where there is not even a single rule about it. We previously mentioned the irrigation of tomato and wheat with water contaminated with antibiotics [25, 47], that is, in an indirect relationship to antibiotic management. We will now talk about the direct handling of antibiotics by the farms and what consequences this has brought to their soil and water. No, the issue is another, for example, many farms have their aqueducts or crop irrigation systems. There are very few studies on pesticide and antibiotic composition, and except for supported studies, where health and environment are the

**170**

pakchoi cabbage. SM2 and SMZ were accumulated more easily by pakchoi cabbage than SDZ. The dissipation half-lives of SMZ (16.8 d) and SM2 (16.7 d) in soil were significantly longer than SDZ (10.8 d).

In a study in an agricultural-livestock region of Japan, loads of veterinary antibiotic oxytetracycline (OTC) in stream waters were investigated [55]. OTC was detected in the concentration range of 2 ng/L to 68 μg/L. An increase in daily OTC loads was observed during the winter as a result of the common veterinary practice of using higher doses of antibiotics as prophylaxis in the prevention of winter diseases. Also, OTC concentrations were observed in stream water near one of the cattle farms. According to the authors, the daily OTC load rate was in a reasonable range to the number of animals, but it was not looked at the antibiotic loads in soil or the associated resistant bacteria.

As we mentioned in the last section the antibiotic accumulation is the second main concern after natural pathogen bacteria. Osterman et al. [56] elaborate one investigation about veterinary antibiotics leached in calcareous Chinese croplands. They found that in daily farm practice, sulfamethazine was constantly detected in the leachate up to 120 ng/L, and conclude that the overall substances were still detected in the soil after 53 days, suggesting that there was no overall rapid and complete dissipation, indicating that strong lixiviation under rainfall does not eliminate the totality of antibiotics and its incomplete dissipation increases risks of their accumulation in soil. Other Chinese work developed antibiotics detection in the agricultural soils from the Yangtze River Delta [57], among which five antibiotics were prevalent in 241 soil samples with a 100% detection rate and total concertation ranging from 4.55 to 2010 ng/g dry weight. The concentrations were as follow: quinolones with mean 48.8 ng/g, tetracyclines with mean 34.9 ng/g, sulfonamides with mean 2.35 ng/g, ciprofloxacin with mean 27.7 ng/g, and oxytetracyclines with a mean of 18.9 ng/g, being the most prevalent the two last ones.

Sarkar et al. [58] did an excellent review of antibiotics in the farm, livestock, aquaculture, and plants, and they concluded that the indiscriminate use of veterinary and human antibiotics not only created multidrug resistant human or animal bacteria, but plant resistant bacteria. Complex and jeopardy manipulation because the human being was transformed the overall bacteria species multidrug-resistant without suspecting. On the other hand, it is not to make the studies unsettling or reassuring that human or livestock antibiotics concentration is an acceptable level when we have to transform rapidly the species and filling the Earth with antibiotics. The most important now is to make clever decisions such as those discussed by Kuppusamy et al. [59]. They comment in their critical review that precisely the veterinary antibiotics are usually poorly sorbed in the animal gut, and the majority is excreted unchanged or as their recalcitrant metabolites in feces and urine.

#### **8. Antibiotics in livestock, poultry, and swine**

Antibiotics are very important in the prescription and treatment, to recover the health of the animals. However, there is no logical explanation for antibiotics as a supplementary feed, except to clarify that the animal biomass increases. There is no scientific explanation about the use and human health of the consumption of beef, chicken or pork fed with no antibiotic supplement. There is a valuable review in these topics especially antibiotics in livestock [58, 60, 61].

There are three main concerns about antibiotics in livestock, which could be in poultry and swine: 1- the high antibiotic concentration in treatment [62], 2- the high concentration in supplementary foods [63], and 3- the extra antibiotics pick out by livestock from water or grass [64]. And a final concern will be, what is the

**173**

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

final concentration of antibiotics in the beef after cooking or treatment in the sausage or deli process. However, most of the antibiotics consumed by livestock are found in the feces [65], indicating poor assimilation, overuse, and uselessness, or little control over their management. If the farmer gives to the animal too much or little antibiotics, it will heal and fatten [61]. Therefore, the excessive cost of antibiotics and their great management on farms is almost unjustifiable, saving a lot of money in the decrease of management that could preserve the health of the troop and the environment by eliminating multi-resistant bacteria from its environment

There is no difference in antibiotics panorama in poultry and swine [67]. For example, Zheng et al. [68] determined the presence of 15 sulfonamides in livestock and poultry manure standardizing a new technique with UPLC-MS/MS plus Fe3O4- MWCNTs. The SAs recovered oscillated from 89 to 119% and the limit of detection of the method was reached 0,5 to 1 μg/kg dry weight, and the limit of quantification was between 1 and 3 μg/kg dry weight. Swine manure contains up to 12 antibiotics, was detected by Rasschaert et al. [69] work. The most frequent antibiotic detected were doxycycline, sulfadiazine, and lincomycin. Doxycycline was found in the highest concentration in manure with a mean of 1476 μg/kg from 8 to 13632 μg/kg, tylosin was found in manure with mean concentrations of 784 μg/kg from 17 to 5599 μg/kg, oxytetracycline was found in manure with mean concentrations of 482 μg/kg from 11 to 3865 μg/kg, lincomycin, was found in manure with mean concentrations of 177 μg/kg manure from 9 to 3154 μg/kg. The remained 18 antibiotics were found

Aquaculture is another prominent fish and meat business and veterinary antibiotics are also used in aquaculture for the preservation of Salmonidae, and other large-scale cultured species. Currently, aquaculture almost reaches the same level of production as fishing, and likely it will exceed the production of world fisheries in the coming years (FAO) (http://www.fao.org/faostat/en/#data/CL). Chen et al. [70], investigate the bioaccumulation of ciprofloxacin and enrofloxacin in some tissues of culture grass carp such as plasma, bile, liver, and muscle tissues, They calculated the mean values of log bioaccumulation factors (Log BAFs) for these antibiotics and main results were for plasma in the range of 0,43-3,70, for bile in the range 0,36-4,75, for liver in the range − 0,31-4,48, and for muscle in the range 0,23- 4,33. This work also calculated hazard quotients, human health risk evaluation, however, the authors state that those grass carp do not pose risk for human health

Sankar et al. [58] reviewed other previous articles reporting that Kurunasagar et al. [59], published the use and application of cotrimoxazole, chloramphenicol, streptomycin, erythromycin being already a habit in fish aquaculture in India. But as declared Burridge et al. [71], "the use and potential effects of these compounds are herein summarized for the four major salmon producing nations: Norway, Chile, UK and Canada" and state that around 75 percent of the antibiotics fed to fish are excreted into the water. On the other hand, Romero et al. [72], looked the effect of oxytetracycline by HSP70:GFP expression in fish larvae after 48 hours, and how oxytetracycline-triggered the stress and the immune response. In consequence, they believe that is possible new alternative practices for the prevention in aquaculture due to the use, overuse, or abuse of antibiotics, which promote the contamination of the environment and rise resistant bacteria. They consider alternative solutions such as developing strict regulations controlling

in manure with mean concentrations of less than 100 μg/kg.

and clarifying that very little has been published in this regard.

**9. Antibiotics in aquaculture or fish-farming**

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

decontaminated [66].

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

final concentration of antibiotics in the beef after cooking or treatment in the sausage or deli process. However, most of the antibiotics consumed by livestock are found in the feces [65], indicating poor assimilation, overuse, and uselessness, or little control over their management. If the farmer gives to the animal too much or little antibiotics, it will heal and fatten [61]. Therefore, the excessive cost of antibiotics and their great management on farms is almost unjustifiable, saving a lot of money in the decrease of management that could preserve the health of the troop and the environment by eliminating multi-resistant bacteria from its environment decontaminated [66].

There is no difference in antibiotics panorama in poultry and swine [67]. For example, Zheng et al. [68] determined the presence of 15 sulfonamides in livestock and poultry manure standardizing a new technique with UPLC-MS/MS plus Fe3O4- MWCNTs. The SAs recovered oscillated from 89 to 119% and the limit of detection of the method was reached 0,5 to 1 μg/kg dry weight, and the limit of quantification was between 1 and 3 μg/kg dry weight. Swine manure contains up to 12 antibiotics, was detected by Rasschaert et al. [69] work. The most frequent antibiotic detected were doxycycline, sulfadiazine, and lincomycin. Doxycycline was found in the highest concentration in manure with a mean of 1476 μg/kg from 8 to 13632 μg/kg, tylosin was found in manure with mean concentrations of 784 μg/kg from 17 to 5599 μg/kg, oxytetracycline was found in manure with mean concentrations of 482 μg/kg from 11 to 3865 μg/kg, lincomycin, was found in manure with mean concentrations of 177 μg/kg manure from 9 to 3154 μg/kg. The remained 18 antibiotics were found in manure with mean concentrations of less than 100 μg/kg.

#### **9. Antibiotics in aquaculture or fish-farming**

Aquaculture is another prominent fish and meat business and veterinary antibiotics are also used in aquaculture for the preservation of Salmonidae, and other large-scale cultured species. Currently, aquaculture almost reaches the same level of production as fishing, and likely it will exceed the production of world fisheries in the coming years (FAO) (http://www.fao.org/faostat/en/#data/CL). Chen et al. [70], investigate the bioaccumulation of ciprofloxacin and enrofloxacin in some tissues of culture grass carp such as plasma, bile, liver, and muscle tissues, They calculated the mean values of log bioaccumulation factors (Log BAFs) for these antibiotics and main results were for plasma in the range of 0,43-3,70, for bile in the range 0,36-4,75, for liver in the range − 0,31-4,48, and for muscle in the range 0,23- 4,33. This work also calculated hazard quotients, human health risk evaluation, however, the authors state that those grass carp do not pose risk for human health and clarifying that very little has been published in this regard.

Sankar et al. [58] reviewed other previous articles reporting that Kurunasagar et al. [59], published the use and application of cotrimoxazole, chloramphenicol, streptomycin, erythromycin being already a habit in fish aquaculture in India. But as declared Burridge et al. [71], "the use and potential effects of these compounds are herein summarized for the four major salmon producing nations: Norway, Chile, UK and Canada" and state that around 75 percent of the antibiotics fed to fish are excreted into the water. On the other hand, Romero et al. [72], looked the effect of oxytetracycline by HSP70:GFP expression in fish larvae after 48 hours, and how oxytetracycline-triggered the stress and the immune response. In consequence, they believe that is possible new alternative practices for the prevention in aquaculture due to the use, overuse, or abuse of antibiotics, which promote the contamination of the environment and rise resistant bacteria. They consider alternative solutions such as developing strict regulations controlling

*Emerging Contaminants*

significantly longer than SDZ (10.8 d).

or the associated resistant bacteria.

pakchoi cabbage. SM2 and SMZ were accumulated more easily by pakchoi cabbage than SDZ. The dissipation half-lives of SMZ (16.8 d) and SM2 (16.7 d) in soil were

In a study in an agricultural-livestock region of Japan, loads of veterinary antibiotic oxytetracycline (OTC) in stream waters were investigated [55]. OTC was detected in the concentration range of 2 ng/L to 68 μg/L. An increase in daily OTC loads was observed during the winter as a result of the common veterinary practice of using higher doses of antibiotics as prophylaxis in the prevention of winter diseases. Also, OTC concentrations were observed in stream water near one of the cattle farms. According to the authors, the daily OTC load rate was in a reasonable range to the number of animals, but it was not looked at the antibiotic loads in soil

As we mentioned in the last section the antibiotic accumulation is the second main concern after natural pathogen bacteria. Osterman et al. [56] elaborate one investigation about veterinary antibiotics leached in calcareous Chinese croplands. They found that in daily farm practice, sulfamethazine was constantly detected in the leachate up to 120 ng/L, and conclude that the overall substances were still detected in the soil after 53 days, suggesting that there was no overall rapid and complete dissipation, indicating that strong lixiviation under rainfall does not eliminate the totality of antibiotics and its incomplete dissipation increases risks of their accumulation in soil. Other Chinese work developed antibiotics detection in the agricultural soils from the Yangtze River Delta [57], among which five antibiotics were prevalent in 241 soil samples with a 100% detection rate and total concertation ranging from 4.55 to 2010 ng/g dry weight. The concentrations were as follow: quinolones with mean 48.8 ng/g, tetracyclines with mean 34.9 ng/g, sulfonamides with mean 2.35 ng/g, ciprofloxacin with mean 27.7 ng/g, and oxytetracyclines with a

Sarkar et al. [58] did an excellent review of antibiotics in the farm, livestock, aquaculture, and plants, and they concluded that the indiscriminate use of veterinary and human antibiotics not only created multidrug resistant human or animal bacteria, but plant resistant bacteria. Complex and jeopardy manipulation because the human being was transformed the overall bacteria species multidrug-resistant without suspecting. On the other hand, it is not to make the studies unsettling or reassuring that human or livestock antibiotics concentration is an acceptable level when we have to transform rapidly the species and filling the Earth with antibiotics. The most important now is to make clever decisions such as those discussed by Kuppusamy et al. [59]. They comment in their critical review that precisely the veterinary antibiotics are usually poorly sorbed in the animal gut, and the majority is excreted unchanged or as their recalcitrant metabolites in feces and urine.

Antibiotics are very important in the prescription and treatment, to recover the health of the animals. However, there is no logical explanation for antibiotics as a supplementary feed, except to clarify that the animal biomass increases. There is no scientific explanation about the use and human health of the consumption of beef, chicken or pork fed with no antibiotic supplement. There is a valuable review in

There are three main concerns about antibiotics in livestock, which could be in poultry and swine: 1- the high antibiotic concentration in treatment [62], 2- the high concentration in supplementary foods [63], and 3- the extra antibiotics pick out by livestock from water or grass [64]. And a final concern will be, what is the

mean of 18.9 ng/g, being the most prevalent the two last ones.

**8. Antibiotics in livestock, poultry, and swine**

these topics especially antibiotics in livestock [58, 60, 61].

**172**

the use of antibiotics and having led to only a few antibiotics being licensed for use in aquaculture and preventing the high proportions of antibiotic-resistant bacteria which still persist in sediments and farm surroundings and suggesting the implementation of rearing practices that reduce the level of stress from fish larvae to adult, which could reduce the likelihood of infections requiring antibiotic treatment.
