A COMPARATIVE STUDY OF THE BIOACCUMULATION OF PCB 126 IN THE INTESTINE TISSUE OF FRESHWATER FISH RASBORA DANICONIUS AND PUNTIUS TICTO (HAM.)

A COMPARATIVE STUDY OF THE BIOACCUMULATION OF PCB 126 IN THE INTESTINE TISSUE OF FRESHWATER FISH RASBORA DANICONIUS AND PUNTIUS TICTO (HAM.)

Advait Bhagade

Department of Zoology, St. Francis De Sales College, Seminary Hills, Nagpur - 440006, Maharashtra, India.

ABSTRACT: Two species of freshwater fish, Rasbora daniconius and Puntius ticto, were procured from a local freshwater body. They were subjected to chronic exposure by a daily sub-lethal dose of PCB 126, by use of a continuous flow-through method, for a period of 30 days. Estimation of bioaccumulation of PCB 126 in the intestine tissues of the fish was carried out at intervals of every 5 days using suitable clean-up methods. The extent of bioaccumulation of PCB 126 per gram wet weight of tissue in the eluate obtained after the cleanup process was assessed with the help of GC-MS. Both species of the test fish showed bioaccumulation in varying concentrations in the intestine tissue. A comparison of the PCB 126 values at the end of the experimental period of 30 days shows that there is an appreciably greater extent of bioaccumulation of PCB 126 in intestine tissue of the freshwater fish, Rasbora daniconius as compared to that of Puntius ticto.

Rasbora daniconius, Puntius ticto, PCB 126, Chronic exposure, bioaccumulation, GCMS

INTRODUCTION: A large volume of work is available where analysis of the effects of various pollutants on organisms has been studied. Further, this work on effects on aquatic organisms is also considerable. A major part of the work has been carried out on marine fish and lesser so on freshwater fish. Due to the aquatic habitat of fish and the unique properties of water, pollutants are seen to enter the bodies of fish from the surrounding water, bioaccumulate in their bodies and biomagnify over different trophic levels of the food chain, ultimately reaching the diet of man. The study of degrees of bioaccumulation of various pollutants, and their effects on organisms, has thus become an important part of ecological studies. The pollutants include a variety of substances, such as pesticides, heavy metals, etc.

Fish, being aquatic organisms, are directly exposed to pollutants present in the water primarily through gills, during respiration, which is a continuous process. Secondarily, direct exposure of the body to pollutants is also at the site of the alimentary canal, where they would enter through or with food. The metabolic pathway through which these substances may travel is first through the circulatory system, where they may be deposited by blood from gills and intestinal tissue, into the liver for bio-transformation into less harmful substances, and then to the kidney for excretion to the outside. In the present comparative study, bioaccumulation of PCB 126 in the intestine tissue of the freshwater fish Rasbora daniconius and Puntius ticto has been considered.

MATERIALS AND METHODS: Fish of both species were obtained from local freshwater bodies. Their easy availability, small size, less weight, ease of stocking and handling, etc., rendered them favorable for the present study. The fish were acclimatized in dechlorinated tap water for about ten days at room temperature.

The well-known acronym PCB (Poly Chlorinated Biphenyl) stands for a class of 209 organochlorine chemicals existing as molecules called congeners. They are a class of non-polar chlorinated hydrocarbons with a biphenyl nucleus of which one or more of the 10 Hydrogen atoms are replaced with chlorine. They have a general formula C₁₂H₁₀-nCl_n where n may range from 1 to 10. The complete names of the congeners as per the IUPAC nomenclature are rather unwieldy, and hence the congeners are referred to by researchers with simpler and shorter names, using numerical codes, brand names, or abbreviations. The chemical formula of 3,3’,4,4’,5- pentachlorobiphenyl, better known as PCB 126, is C₁₂ H₇C_l5. PCB congeners are odorless, tasteless, clear to pale-yellow, viscous liquids. PCBs were widely used as dielectric and coolant fluids, for example, in transformers, capacitors, and electric motors, and have found their way into water bodies through various routes of pollution.

FIG. 1: GENERAL STRUCTURE OF POLYCHLORINATED BIPHENYL

PCB 126 is not soluble in water. A stock of the test solution was therefore prepared using 1 mg /ml of PCB 126 with Dichloromethane (MERCK) as an organic solvent and then diluted for use as per requirement. The test organisms were then exposed to varying concentrations of each solution by performing acute bioassays at 24, 48, 72, and 96 h intervals. PCB 126 of Dr. Ehrenstorfer (Germany) make used for the present work.

A sub-lethal concentration, based on the LC₅₀ values obtained during acute bioassay, was arrived at. Based on these values, a sub-lethal concentration of the substance under study was determined, and further chronic toxicity tests were carried out on the test fish over 30 days, using a continuous flow-through method, with tissue samples taken at intervals of 5, 10, 15, 20, 25 and 30 days.

Analysis of the effects of various pollutants has been carried out using various methods. There are many references available in the literature on the use of bioassays for evaluation of soil and sediment toxicity 1-4, and integrating bioassays with other techniques using fish and invertebrates to assess environmental risks and damage ^5-8. However, few references are available for bioassays using the pollutant substance for direct exposure of test organisms. Bioassays to determine acute toxicity after 96 h exposures to determine LC₅₀ values ⁹, and use of continuous flow-through bioassays ¹⁰, are some of these methods.

The use of GC and GC-MS to estimate the degree of bioconcentration has been widely accepted ^{11, 12}. Literature available confirms that PCBs are toxic and bioaccumulate in organisms ^13-24.

The study was carried out first with the help of acute bioassays of 96-hour duration to determine LC₅₀ values as per standard methods available in literature ^{25, 26}, and based on such values, a subsequent chronic bioassay of 30 days using a dosing apparatus with a continuous flow through method ²⁷ was carried out. A sublethal dose of 12.5 µg l^-1 of PCB 126 was introduced into the water for each fish species under study daily, over 30 days, using a continuous flow-through method. Appropriate controls were also run in parallel.

Studies show that the path followed by pollutant substances through the fish begins with entrance through the gills or the mouth into the alimentary canal, followed by absorption or accumulation, metabolism by the liver, transfer of pollutants or their metabolites to the liver, and, finally, excretion through kidneys. PCBs are seen to bioaccumulate in both plant and animal biota ^28-34 and expose man ^35-40, who is at the end of many food chains, too much higher levels as compared to trace levels present in the environment. There are indications that chronic exposure to PCB mixtures (Aroclor 1254) may lead to toxicity, and the PCBs may persist in fish tissues for about 3 months ⁴¹. Such bioaccumulation may lead to carcinogenic and other deleterious effects in men ^42-48. This has recently resulted in a quest for remediation of the effects of PCBs and similar pollutants in the environment ^49-50.

The intestine tissue of the test organisms, i.e., freshwater fish Rasbora daniconius and Puntius ticto were obtained every 5 days over a period of 30 days. Tissues were weighed, and extracts were obtained after clean up using Dichloromethane through Celite columns. Analysis of these extracts, using GCMS for analysis, has shown bio-accumulation of the above compounds in different tissues over a period of time.

Observations: A significant bioaccumulation of PCB 126 was observed on analysis of the intestine tissues of Rasbora daniconius and Puntius ticto, as is evident from the Chromatograms obtained after analysis of tissue extracts on GC-MS Fig. 1 and 2.

A comparison of the values of bioaccumulation in both fish is shown in Table 1.

TABLE 1: BIOACCUMULATION OF PCB 126 IN INTESTINE OF RASBORA DANICONIUS AND PUNTIUS TICTO

A graphical representation of the accumulation of PCB 126 in the four tissues studied has been given in Fig. 3.

FIG. 3: GRAPHICAL COMPARISON OF BIO-ACCUMULATION OF PCB 126 IN INTESTINE TISSUE OF RASBORAS DANICONIUS AND PUNTIUS TICTO

DISCUSSION: In Rasbora daniconius, bio-accumulation of PCB 126 was not detected in the intestine tissue in the first 5 days. However, there was an incremental and sharp increase in the bioaccumulation of approximately 5 µgg^-1 wet weight every subsequent fifth day, till on the 30^th day, tissue showed bioaccumulation of 23.95 µg g^-1 wet weight.

In Puntius ticto, bioaccumulation was seen to be very gradual, from 1.88 µg g^-1 wet weight on the 5^th day of exposure to 10.07 µg g^-1 wet weight of intestine tissue on the 30^th day.

RESULTS: Fish may be subject to direct exposure to pollutants at the site of the alimentary canal, where pollutants would enter through or with food. In the present study, it can be inferred that pollutants bioaccumulate within the intestine tissue of fish.

PCB 126 was seen to accumulate to a lesser extent in Puntius ticto as compared to Rasbora daniconius, indicating that the biotransformation pathways in the former are more efficient than the latter and that PCB 126 may be metabolized through the intestine tissue to subsequent sites such as the liver and kidney, more in case of Puntius ticto than in case of Rasbora daniconius.

CONCLUSION: In conclusion, it can be said that the bioaccumulation of PCB 126 in the intestine tissue of the fish species studied gives an indication of the propensity of the pollutant to accumulate in tissue, albeit to varying extents. This may therefore serve as a warning for controlled use of PCBs and their proper disposal, failing which, they are sure to reach man through various types of food chains and cause deleterious effects on health.

ACKNOWLEDGEMENT: I am grateful for the support and invaluable guidance of Late Dr. Shanta Satyanarayan, Retd. Deputy Director, NEERI, Nagpur in performing the above work.

CONFLICTS OF INTEREST: I hereby declare that there is no conflict of interest with any other person, institution or authority in the performance of the above work.

REFERENCES:

1. Samelin J: Biological responses of midge (Chironomous riparius) and lamprey (Lampetra fluviatilis) larvae in ecotoxicity assessment of PCDD/F-, PCB- and Hg- contaminated river sediments. Environmental Science and Pollution Research 2016; 23(18): 18379-93.
2. Vethaak AD: Toxicity profiling of marine surface sediments: A case study using rapid screening bioassays of exhaustive total extracts, elutriates and passive sampler extracts. Marine Environmental Research 2017; 124: 81-91.
3. Ferras MA: Sediment toxicity Identification evaluation (TIE Phases I and II) based on microscale bioassays for diagnosing causes of toxicity in coastal areas affected by domestic sewage. Environmental Toxicology and Chemistry 2017; 36(7): 1820-32
4. McQueen A: Evaluation of dredged sediment for aquatic placement: interpreting contaminant bioaccumulation. Environmental Monitoring and Assessment 2020; 192: 277.
5. Ianuzzi TJ: Assessing measurable adverse changes to benthic invertebrate communities based on site-specific sediment toxicity testing and community data at the Anniston, Alabama PCB site. Human and environmental risk assessment: An international Journal 2018; 24(2): 291-306.
6. Jafarabadi AR: First polychlorinated biphenyls (PCBs) monitoring in seawater, surface sediments and marine fish communities of the Persian Gulf: Distribution, levels, congener profile and health risk assessment. Environmental Pollution 2019; 253: 78-88.
7. Wang D: Ecological and health risk assessment of PAHs, OVPs, and PCBs in Taihu lake basin. Ecological Indicators 2018; 92: 171-80.
8. Lin W: Quantification of the combined toxic effect of polychlorinated biphenyls and nano-sized polystyrene on Daphnia magna. Journal of Hazardous Materials 2019; 364: 531-36.
9. Vieira LR: Acute effects of Benzo[a]pyrene, anthracene and a fuel oil on biomarkers of the common goby Pomatoschistus microps. Science of the Total Environment 2008, 395(2-3): 87-100.
10. Brenniman G: A continuous flow bioassay method to evaluate the effects of outboard motor exhausts and selected aromatic toxicants on fish. Water Research 1976, 10(2): 165-69.
11. Maack L and Sonzogni WC: Analysis of polychloro-biphenyl congeners in Wisconsin fish. Archives of Environmental Contamination and Toxicology 1988; 17(6): 711-19.
12. Eqani SAM: Uptake of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) by river water fish: The case of River Chenab. Science of the Total Environment 2013; 450-51: 83-91.
13. Pagano JJ: Age-Corrected Trends and Toxic Equivalence of PCDD/F and CP-PCBs in Lake Trout and Walleye from the Great Lakes: 2004-2014. Environmental Science and Technology 2018; 52(2): 712-21.
14. Olantunji OS: Evaluation of Selected polychlorinated biphenyls (PCBs) congeners and dichlorodiphenyl-trichloroethane (DDT) in fresh root and leafy vegetables using GC-MS. Scientific Reports 2019; 538.
15. Zeying H: Stereoselective bioaccumulation of chiral PCB 91 in earthworm and its metabolomic and Lipidomic responses. Environmental Pollution 2018; 238: 421-30.
16. Giandomenico S: Metals and PCB levels in some edible marine organisms from the Ionian sea: Dietary intake evaluation and risk for consumers. Environmental Science Pollution Research International 2016; 23(13): 12596-612.
17. Maisano M: PCB and OCP accumulation and evidence of hepatic alteration in the Atlantic blue fin tuna thynnus, from the Mediterranean sea. Marine Environmental Research 2016; 121: 40-48.
18. Cullen JA: Integration of multi tissue PAH and PCB burdens with biomarker activity in three coastal Shark species from the north Western Gulf Of Mexico. Science of the Total Environment 2019; 650(1): 1158-72.
19. Zhao Y: Comparative developmental toxicity of eight typical organic pollutants to red sea bream (Pagrosomus major) embryos and larvae. Environmental science and Pollution Research 2017; 24: 9067-78.
20. Xu H: Differential sensitivities to dioxin-like compounds PCB 126 and PeCDF between Tg(cyp1a:gfp) transgenic medaka and zebrafish larvae. Chemosphere 2018; 192: 24-30.
21. Torres P: Bioaccumulation of metals and PCBs in Raja clavata. Science of the Total Environment 2016; 573: 1021-30.
22. Jepson P: PCB pollution continues to impact populations of orcas and other dolphins in European waters. Scientific Reports 2016; 6: 18573.
23. Dabrowska H: An integrated assessment of pollution and biological effects in flounder, mussels and sediment in the southern Baltic Sea coastal area. Environmental Science Pollution Research 2017; 24: 3626-39.
24. Hayman NT: Seasonal Toxicity Observed with Amphipods (Eohaustorius estuarius) at Paleta Creek, San Diego Bay, USA. Environmental Toxicology and Chemistry 2020; 39(1): 229-39.
25. Davis JC and Mason BJ: Bioassay Procedures to Evaluate Acute Toxicity of Neutralized Bleached Kraft Pulp Mill Effluent to Pacific Salmon. Journal of the Fisheries Research Board of Canada 1973; 30(10): 1565-73.
26. Jung-Suk L: Acute toxicity of heavy metals, tributyltin, ammonia and polycyclic aromatic hydrocarbons to benthic amphipod Grandidierella japonica. Ocean Science 2005; 40(2).
27. Murty AS: Toxicity of pesticides to fish, Vol. I. CRC Press Inc. Boca Raton, Florida 1986.
28. Piskorska-Pliszczynska J: Dioxins and PCBs in ostrich meat and eggs: levels and implications. Food Additives & Contaminants (Part A): 2017; 34(12).
29. Cigliano L: Evaluation of serum markers of blood redox homeostasis and inflammation in PCB naturally contaminated heifers undergoing decontamination. Science of the Total Environment 2016; 542(A): 653-64.
30. Bartalini A: Evaluation of PCDD/Fs, dioxin-like PCBs and PBDEs in sperm whales from the Mediterranean Sea. Science of the Total Environment 2019; 653:1417-1425.
31. Adams CM: Toxicological effects of polychlorinated biphenyls (PCBs) on freshwater turtles in the United States. Chemosphere 2016; 154: 148-54.
32. Lavandier R: PCB and PBDE contamination in Tursiops truncatus and Stenella fontalis, two data deficient threatened dolphin species from the Brazilian coast. Ecotoxicology and Environmental Safety 2019; 167: 485-93.
33. Girolami F: Identification of candidate biomarkers of the exposure to PCBs in contaminated cattle: A gene expression- and proteomic-based approach. Science of the Total Environment 2018; 660-641: 22-30.
34. Dean KM: Comparative lethality of In ovo Exposure to PCB 126, PCB 77, and 2 Environmentally relevant PCB Mixtures in Japanese Quail (Coturnix japonica). Environmental Toxicology and Chemistry 2019; 38(12): 2637-50.
35. Adetutu IA: Carcinogenicity of dioxin-like polychlorinated biphentls in transformer soil in vicinity of Port Harcourt, Choba, Nigeria. Chemistry International 2020; 6(3): 144-50.
36. Man YB: A pilot study on health risk assessment based on body loadings of PCBs of lactating mothers at Taizhou, China, the world’s major site for recycling transformers. Environmental Pollution 2017; 227: 364-71.
37. Ahmed RG: Gestational 3,3’,4,4’,5-pentacholorobiphenyl (PCB 126) exposure disrupts fetoplacental unit: Fetal throid-cytokines dysfunction. Life Sciences 2018; 192: 213-20.
38. Anzalone DA: Polychlorinated biphenyls (PCBs) alter DNA methylation and genomic integrity of sheep fetal cells in a simplified in-vitro model of pregnancy exposure. Toxicology in Vitro 2018; 46: 39-46.
39. Raffetti E: Polychlorinated biphenyls (PCBs) and risk of hypertension: A population-based cohort study in a North Italian highly polluted area. Science of the Total Environment 2020; 714: 13660.
40. Petrosino V: The role of heavy metals and polychlorinated biphenyls (PCBs) in the oncogenesis of head and neck tumors and thyroid diseases: A pilot study. Biometals 2018; 31: 285-95.
41. Hansen DJ: Chronic toxicity, uptake, and retention of aroclor® 1254 in two estuarine fishes. Bulletin of Environmental Contamination and Toxicology 1971; 6(2): 113-19.
42. Zeljezic D: Persistent Organic pollutants In Placentas sampled from women In Croatia and an evaluation of their DNA damaging potential in-vitro. Archives of Environmental Contamination and Toxicology 2018; 74: 284-91.
43. Emece-Huja P: Epidemiologic evaluation of NHANES for environmental factors and periodontal disease. Science Reports 2019; 9(1): 8227.
44. Pencikova K: In-vitro profiling of toxic effects of prominent environmental lower chlorinated PCB congeners linked with endocrine disruption and tumor promotion. Environmental Pollution 2018; 237: 473-86.
45. Lauby-Secretan B: Use of Mechanistic data in the IARC evaluations of the carcinogenicity of polychlorinated biphenyls and related compounds. Environmental Science and Pollution Research 2016; 23: 2220-29.
46. Jiang L: Toxic effects of polychlorinated biphenyls (Aroclor 1254) on human sperm motility. Asian Journal of Andrology 2017; 19(5): 561-66.
47. Walter KM: Association of Polybrominated Diphenyl Ethers (PBDEs) and Polychlorinated Biphenyls (PCBs) with Hyperthyroidism in Domestic Felines, Sentinels for Thyroid Hormone Disruption. BMC Veterinary Research 2017; 13: 20.
48. Kang Y: Health risks and source identification of dietary exposure to indicator polychlorinated biphenyls (PCBs) in Lanzhou, China. Environmental Geochemistry and Health 2020; 42: 681-92.
49. Khammar S: Preparation and surface engineering of CM- ᵦ-CD funtionalized Fe₃O₄@TiO₂ nanoparticles for photocatalytic degradation of polychlorinated biphenyls (PCBs) from transformer oil. Journal of Hazardous Chemicals 2020; 394: 122422.
50. Sredlova K: Biodegradation of PCBs in contaminated water using spent oyster mushroom substrate and a trickle-bed bioreactor. Water Research 2020; 170: 115274.
    

    ---

    How to cite this article:

    Bhagade A: A comparative study of the bioaccumulation of PCB 126 in the intestine tissue of freshwater fish Rasbora daniconius and Puntius ticto (Ham.). Int J Pharm Sci & Res 2021; 12(2): 1196-00. doi: 10.13040/IJPSR.0975-8232.12(2).1196-00.

    ---

    All © 2013 are reserved by the International Journal of Pharmaceutical Sciences and Research. This Journal licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.

    ---