Accumulation and half-lives of 13 pesticides in muscle tissue of freshwater fishes through food exposure.

Fish are often exposed to various molecules like pesticides. Some of these compounds get biomagnified within aquatic food web, inducing health hazards of consumers. However, behaviors of many pesticides are still unknown. This work aims to study the uptake and the elimination of some of them in muscle tissue of edible fish (azoxystrobin, clomazone, diflufenican, dimethachlor, carbendazim, iprodion, isoproturon, mesosulfuron-methyl, metazachlor, napropamid, quizalofop, and thifensulfuron-methyl). Two freshwater fish species (Perca fluviatilis and Cyprinus carpio) were exposed to a mixture of these 13 pesticides, via multi-contaminated pellets, and then, eliminated. Compounds were measured in food, water and muscle tissue using multi-residues methods. Kinetics, biomagnification factors (BMFs) and half-lives (t1/2) were estimated and they did not show a large difference between the species. Muscular BMFs ranged from 2 × 10(-6) (mesosulfuron-methyl in perch) to 1 × 10(-3) (isoproturon and napropamid in perch) and t1/2 ranged from 0.8 (mesosulfuron-methyl in perch) to 40.3d (napropamid in carp). BMFs were also modeled as a function of Kow value. All BMF values were explained by the model, except for diflufenican which had a BMF lower than that expected by our modeling work, probably due to an efficient metabolism. Results led to the conclusion that none of these chemicals would probably be biomagnified within aquatic food webs.

Pesticide pressure and fish farming in barrage pond in northeastern France. Part III: how management can affect pesticide profiles in edible fish?

PURPOSE: The quality of fish produced in ponds needs to be ensured. Indeed, pond is often strongly connected to an agricultural watershed, and pesticides are a main health and environmental issue of concern. In this context, the purpose of this study is to highlight the management practices which could impact the pesticide contamination profiles in edible fish and to give recommendations for better practices. METHODS: A principal component analysis, coupled to a hierarchical cluster analysis, was performed to evaluate temporal evolution of contamination profiles and to assess variability among fish species and among sites according to watershed characteristics. The explicative variables correspond to muscular concentrations of pesticides (azoxystrobin, clomazone, diflufenican, carbendazim, isoproturon, metazachlor, napropamid) in three species of fish (Perca fluviatilis, Cyprinus carpio and Rutilus rutilus), caught in five ponds during two sampling campaigns. Management data are added variables in order to discuss about parameters suspected to be implicated in the contamination profiles recorded. RESULTS: This work shows that high amounts of pesticides applied, short crop rotation durations and bare soil practices led to contamination of sediments and fish and were associated to a "bad" management of watershed. Breeding fish that had low masses and establishing the fishing period at the end of winter seemed to be "bad" management of pond. Aggravating topological parameters were big watershed coupled to small pond and high proportions of sand soils in the watershed. CONCLUSIONS: Reducing amounts of pesticide used (e.g. policy agency plans, farmer acceptance), favouring long-term rotations and inter-cultures, adapting pond creation and fish farming practices to watershed management and topography all could reduce pesticide levels in edible fish and contribute to a better sustainability of the extensive fish farming in pond.

Pesticide pressure and fish farming in barrage pond in Northeastern France. Part II: residues of 13 pesticides in water, sediments, edible fish and their relationships.

Residues of pesticides in fish farming productions from barrage ponds are seldom studied in spite of increasing health questionings and environmental concerns. The purpose of this study is to establish the pesticide contamination profiles of sediments and edible fish from five ponds in Northeastern France. Multi-residues method and liquid chromatography-tandem mass spectrometry analysis were used to quantify 13 pesticides (azoxystrobin, carbendazim, clomazone, diflufenican, dimethachlor, fluroxypyr, iprodion, isoproturon, mesosulfuron-methyl, metazachlor, napropamid, quizalofop and thifensulfuron-methyl). Ten sediments and 143 muscles samples were analysed, corresponding to two successive fishing campaigns (first fishing date and second fishing date (P2), about 1 year later) on five sites (noted C-0, C-25, C-45, C-75 and C-85 to express the increasing gradient of crop area). Isoproturon was present in all sediments samples (1.8-56.4 µg/kg dry weight). During P2 period, carbendazim was quantified in the fish of site C-0 (0.09 ± 0.02, 0.2 ± 0.1 and 0.17 ± 0.06 µg/kg wet weight (ww) for roach, carp and perch, respectively). Metazachlor was only quantified in perch of the site C-25 (0.13 ± 0.02 µg/kg ww). Concentrations of isoproturon were similar for the sites C-45 and C-75 with 0.4 ± 0.1 and 0.75 ± 0.06 µg/kg ww for carp and perch, respectively. Contamination of fish reflected generally concentrations in surroundings. Isoproturon was the most concentrated and its main source was water for perch while carp was exposed through both water and sediments, highlighting their life strategies in pond.

Organochlorine pesticides and polychlorinated biphenyls in sediments and fish from freshwater cultured fish ponds in different agricultural contexts in north-eastern France.

Organochlorine pesticides (HCB, HCH with α-, ß-, and γ isomers, heptachlor, cis-heptachlor epoxyde, trans-heptachlor epoxyde, endosulfan with α- and ß isomers, sulfate endosulfan, o,p'-DDT, p,p'-DDT, o,p'-DDE, p,p'-DDE, o,p'-DDD, p,p'-DDD, chlorothalonil, alachlor, aldrin, dieldrin, methoxychlor, oxychlordane, chlordane with α- and γ isomers, p,p'-dicofol and o,p'-dicofol) and indicators PCBs (IUPAC nos. 28, 52, 101, 118, 138, 153, and 180) were studied both in sediments and muscles of farmed fish species (Cyprinus carpio and Perca fluviatilis). Samples were collected from fish ponds located in the hydrographic basin of the Moselle River (Lorraine Region, France). OCPs and PCBs were present at low concentrations both in sediments and fish muscles. Concerning sediments, ∑DDTs revealed concentrations ranging from 0.2 to 2.30 ng g(-1) dw and ∑PCBs ranged from 0.3 to 3.5 ng g(-1) dw. Concerning fish muscles, the highest concentrations in OCPs were those of p,p'-DDE, with average concentrations of 0.57±0.44 ng g(-1) ww for carp and 0.58±0.29 ng g(-1) ww for perch. The contamination profiles proved to be different depending on the fish species. Indeed, HCH-isomers, HCB, and dieldrin were detected only for the carp and always at low concentrations. For example, the highest concentration of HCHs was observed for ß-HCH with a mean value of 0.64±0.15 ng g(-1) ww for carp. As for PCBs, the levels of ∑PCBs ranged from 0.3 to 6.4 ng g(-1) ww in carp muscles and from 0.90 to 5.60 ng g(-1) ww in perch muscles.

Polycyclic aromatic hydrocarbons and hydroxylated metabolites in the muscle tissue of Eurasian perch (Perca fluviatilis) through dietary exposure during a 56-day period.

Eurasian perch (Perca fluviatilis) was exposed trophically to phenanthrene, pyrene and benzo[a]pyrene. Accumulation kinetics in the muscle tissue of parent PAHs and hydroxylated metabolites were established for 56 days at 3 levels of exposure (0, 100 and 500 µg/kg BW). Benzo[a]pyrene and 3-hydroxy-benzo[a]pyrene were not detected in the muscles. During exposure, there was an increase in phenanthrene, pyrene and their hydroxylated metabolites in the muscle tissue. Low transfer to muscle tissue was observed at equilibrium for phenanthrene (4.4±0.6% and 2.7±0.8%) and pyrene (1.0±0.2% and 0.33±0.09%), depending on the concentrations in the spiked feed.

Pesticide pressure and fish farming in barrage pond in Northeastern France Part I: site characterization and water quality.

PURPOSE: Fish farming in barrage pond is a rearing system commonly used worldwide. Obtaining good water quality is essential to improve sustainability of these ecosystems, both for health of fish consumers and environmental considerations. However, ponds are often located in agricultural landscape, but few study reports impact of pesticide pressure on these ecosystems. This study characterizes five sites in Northeastern France. This work establishes an initial framework for pesticide monitoring with the aim to improve understanding of the fate of pesticides in ponds. METHODS: This framework is based on surveys indicating managements and Geographical Information System (GIS) for five ponds and their watersheds (sites: C-0, C-25, C-45, C-75 and C-85) and completes with some analysis of a large spectrum of pesticide residues in surface waters. RESULTS: Watersheds show a gradient of crop proportion ranging from 0% to 82% of the watershed area, mainly rapeseed, wheat, barley and maize. Ponds were representative of local Northeastern France management. Many pesticides, and also nutrients, were measured in water with concentrations varying between sites and seasons. The sum of quantified molecules ranged from 0.17 µg/l for site C-0 (March) to 8.81 µg/l for site C-25 (October). Concentrations of metaldehyde, quinmerac, isoproturon and bentazon were sometimes above 1 µg/l. CONCLUSIONS: There is a strong connection between pond and watershed, due to water supply throughout the fish production cycle. Sites with small pond/big watershed are the most exposed to acute contamination a few days after spraying because water discharges are not diluted.

Ultrastructural features of hepatocytes in cultured Eurasian perch ( Perca fluviatilis L.) as affected by nutritional and husbandry conditions.

A wide range of factors can be attributed to the syndrome of fatty liver observed in some cultured fish species. The objective of the study was therefore to quantify different hepatocyte ultrastructural features as potentially influenced by twelve nutritional and husbandry factors, in order to discriminate the most influent factors in Eurasian perch (Perca fluviatilis), a typical carnivorous temperate fish species. Twenty-four groups of juveniles (initial weight 57.6 (SD 14.4) g) were intensively reared for 116 d and fed sixteen different isoproteic diets. The distribution of the experimental treatments was based on a multivariate fractional factorial design (L(24) 2(12)) with either high (+1) or low (-1) level of each of the following factors: diet (lipid and protein sources, lipid content, astaxanthin enrichment), feeding level, daily and weekly distribution frequency, fish density, initial weight heterogeneity, temperature, photoperiod, and light spectrum. Liver lipid droplets, glycogen, mitochondria and rough endoplasmic reticulum (RER) were semi-quantified and analysed by a soft imaging system using transmission electronic microscopy photographs. Important variability of hepatocyte ultrastructural features was observed. The present study confirms that the rearing temperature, through its influences in the general metabolic activity, seems to be the main factor modifying mainly lipid droplet accumulation and RER development. However, factors that could be pooled under the designation of factors leading to food accessibility and lipid and protein quality intensify or compensate the effect of temperature.

Effects of geographic source, rearing system, and season on the nutritional quality of wild and farmed Perca fluviatilis.

The effects of season, geographic source (Lake Geneva, Rhine River), and rearing system (extensive, semiextensive, and intensive systems) on the lipid content and FA composition of fillets of Perca fluviatilis were studied. Significant differences in the total lipid content were found between fish coming from the Rhine River and Lake Geneva (1.21 and 1.48%, respectively). Seasonal effects were investigated quarterly for perch sampled in the Rhine River. Intensively reared perch displayed a higher lipid content (1.48%) than the other farmed perch, i.e., 1.26% for a semiextensive system and 1.16% for an extensive system. No significant difference in lipid content was found (i) between lacustrine fish and intensively reared fish or (ii) among fish from the Rhine River and the semiextensive or extensive rearing systems. The main FA were 22:6n-3 (DHA, 21.3-37.1% of total FA), 16:0 (17.7-20.2%), 20:5n-3 (EPA, 9.2-13.2%), 18:1 (8.0-11.5%), 20:4n-6 [arachidonic acid (ARA), 1.9-10.7%], 16:1 (4.3-6.0%), and 18:2n-6 (2.1-6.0%). In comparison with perch coming from the Rhine River, the lacustrine fish were characterized by higher total n-6 PUFA and a lower proportion of both total monounsaturated FA (MUFA) and total n-3 PUFA. Among rearing systems, extensively farmed fish had higher n-6 PUFA and lower n-3 PUFA contents. Wild fish showed higher ARA and 18:2n-6 than farmed fish. They also had significantly more EPA (12.5-13.2%) than farmed perch (9.2-10.9%). For DHA, no difference existed between (i) the lacustrine fish (31.9% of total FA) and the intensively reared fish (33.0%) and (ii) the Rhine (37.1%) and semiextensively reared fish (36%). Effects of size, diet composition, and environmental conditions on the total lipid contents and FA composition are discussed.