Organochlorine Compounds in Beached Plastics and Marine Organisms

Here we compare bioaccumulation factors in marine organisms to partition ratios in marine debris for dichlorodiphenyltrichloroethane and polychlorinated biphenyls. Both organochlorines are synthetic persistent organic pollutants emitted into the environment since the beginning of the last century in approximately equal amounts. Their vast use and dispersion have resulted in approximately similar median concentrations of the two organochlorines in some pelagic organisms, namely in the liver and muscle tissue of fish. Molluscs, on the other hand, show higher median uptake of PCBs (median = 2.34 ng/g) than of DDTs (median = 1.70 ng/g), probably reflecting more localized conditions. We found that the bioaccumulation factors can be several orders of magnitude higher than the partition ratios. For instance, the median concentrations of organochlorines in the different matrices of fish, birds, and mammals are between one to four orders of magnitude higher than those found in marine debris, when lipid-normalized; or up to two orders of magnitude when measured as wet-weight. But, in molluscs, bioaccumulation/partition equals unity, which agrees with previous studies using passive samplers. Future research should focus on reducing sources of uncertainty by 1) homogenization of chemical procedures; 2) better assessment of chemical partition equilibrium between water and polymers in environmental conditions; 3) use of (multi)polymer passive samplers better aimed at mimicking uptake of specific living tissues.

Proximate composition and bioaccumulation of heavy metals in edible Achatina spp in some rural agro-settlements, south-east Nigeria

Background Animals that live and feed on the soil and its constituents and products naturally absorb heavy metals and pass to other organisms linked in the food chains. The present study was designed to examine bioaccumulation of heavy metals levels and proximate composition quality in edible Achatina spp sampled in agro-rural settlements, south-east Nigeria. Results The proximate composition recorded the presence of moisture, protein, crude fibre, fat and oil, ash, carbohydrates, nitrogen and calcium, which were similar across selected Achatina spp except for calcium, which was significantly higher in A. achatina. The bioaccumulation factors of heavy metal contents in snails were generally low (below recommended tolerable limits according to WHO standard). Conclusion The good number of nutrients recorded in proximate composition makes the Achatina spp an alternative to domestically farmed animals. Achatina achatina contained most calcium level compared with Achatina fulica and Achatina marginate. The bioaccumulation factors of heavy metal contents in snails were generally low (below recommended tolerable limits according to WHO standard). Land snails in our study areas were safe for consumption.

Nodulated White Lupin Plants Growing in Contaminated Soils Accumulate Unusually High Mercury Concentrations in Their Nodules, Roots and Especially Cluster Roots

Two white lupin (Lupinus albus L.) cultivars were tested for their capacity to accumulate mercury when grown in Hg-contaminated soils. Plants inoculated with a Bradyrhizobium canariense Hg-tolerant strain or non-inoculated were grown in two highly Hg-contaminated soils. All plants were nodulated and presented a large number of cluster roots. They accumulated up to 600 μg Hg g−1 DW in nodules, 1400 μg Hg g−1 DW in roots and 2550 μg Hg g−1 DW in cluster roots. Soil, and not cultivar or inoculation, was accountable for statistically significant differences. No Hg translocation to leaves or seeds took place. Inoculated L. albus cv. G1 plants were grown hydroponically under cluster root-promoting conditions in the presence of Hg. They accumulated about 500 μg Hg g−1 DW in nodules and roots and up to 1300 μg Hg g−1 DW in cluster roots. No translocation to the aerial parts occurred. Bioaccumulation factors were also extremely high, especially in soils and particularly in cluster roots. To our knowledge, Hg accumulation in cluster roots has not been reported to date. Our results suggest that inoculated white lupin might represent a powerful phytoremediation tool through rhizosequestration of Hg in contaminated soils. Potential uptake and immobilization mechanisms are discussed.

Brief communication: new perspectives on the calculation of bioaccumulation factors for active substances in living organisms

Today, there are no ready-to-use convenient tools in ecotoxicology to diagnose and predict the accumulation and effects of chemical substances on living organisms, accounting for exposure situations that are known to be complex (routes of exposure, metabolization processes, cocktail effects, etc.). Regarding plant protection products in marketing authorization applications, regulation No 283/2013 (EU) defines the data requirements for active substances with a bioaccumulation test on fish according to OECD Test guideline 305. This paper presents new perspectives on the estimation of the bioaccumulation factors via an innovative ready-to-use web tool providing these factors, associated with their uncertainty to facilitate the daily work of regulators, but also of any user, by benefiting of a freely available and user-friendly on-line interface avoiding to invest into underlying mathematical and statistical technicalities. This tool, MOSAICbioacc, is available at https://mosaic.univ-lyon1.fr/bioacc, and can be used by any environmental scientists, ecotoxicologists or managers when accumulation-depuration data are collected and need to be easily and quickly analysed.

Heavy metal distribution and bioaccumulation ability in marine organisms from coastal regions of Hainan and Zhoushan, China

<p>In this study, we analyzed the distribution and bioaccumulation of six heavy metals (Cu, Pb, Zn, Cr, Cd, Hg) in marine organisms from China’s Hainan and Zhoushan coastal regions. Across all marine organism samples, as well as sediment and seawater samples, Zn and Hg ranked highest and lowest in concentration, respectively. Heavy metal distributions in the marine organisms varied by region and species; concentrations were higher (except for Zn) in Zhoushan than in Hainan and in crab than in fish. A marine organism’s ability to digest and eliminate heavy metals (bioaccumulation ability), based on bioaccumulation factors, was significantly higher for heavy metals in seawater than in sediment; higher sediment background values may explain the higher heavy metal concentrations in crab. In general, a marine organism’s bioaccumulation ability was higher for Cu and Zn and lower for Pb in China.</p>