Similarity Analysis of Pah and PCB Bioaccumulation Patterns in Sediment-Exposed Chironomus Tentans Larvae

Abstract

Abstract-Larvae of the aquatic insect Chironomus tentans (Insecta: Diptera: Chironomidae) were exposed at the third or fourth instar stage to sediments collected near the outfalls of two aluminum foundries and an aluminum fabrication plant. Biota and sediment bioaccumulation factors (BFs), based on wet tissue weights and dry sediment weights, ranged from 0.07 to 0.27 for polycyclic aromatic hydrocarbons (PAHs) and from 0.22 to 1.42 for polychlorinated biphenyls (PCBs). A higher rate of metabolism of PAHs compared with PCBs could explain the differences in BF values for the two groups of chemicals. It was found, using community similarity procedures from the field of ecology, that the congener patterns for PAHs and PCBs bioaccumulated by the larvae differed from the pattern of the same compounds in the sediments to which they were exposed. Affinity analysis indicated that the larvae favored the higher molecular weight PAH and PCB congeners. Preferential ingestion of sediments with defined particle size ranges, metabolism, and octanol/water partition coefficients (log K ow ) are factors that may have influenced the bioaccumulation patterns. However, no single factor could adequately account for the differences between the larval and sediment patterns.

Accumulation and depuration of sediment‐sorbed C12‐ and C16‐polychlorinated alkanes by oligochaetes (Lumbriculus variegatus)

“…Therefore, relative abundance of individual components of CP mixtures in benthic invertebrates would be expected to be different than those observed in sediment or commercial products. Oliver [22] and Wood et al [23] reported changes in relative abundance of PCBs congeners and polycyclic aromatic hydrocarbons between sediment and benthic invertebrates due to differences in bioavailability and biotransformation rates of individual compounds.…”

Evaluation of polychlorinated biphenyl bioaccumulation patterns in white sea urchins (Lytechinus pictus) using multiple approaches

“…Chemical concentrations below the detection limit were assigned a value of zero. Apparently, similarity values tend to plateau at 82% based on numerous previous studies [29], and samples with similarity values ≥; 82% are considered essentially identical.…”

“…Thus, by assigning these attributes to the chemicals, the bioaccumulation data are made amenable to ecological similarity and preference analysis. Similarity between the urchin and sediment PCB patterns were quantified by calculating the Bray‐Curtis similarity coefficients [29] for each sediment‐urchin paired data set. The general equation used was where S jk is the percentage similarity of the PCB patterns in the urchins and sediment; X j and X k are the prominence values [ D # F ] for the individual congeners in samples j and k, respectively; D is the concentration of a given congener; and F is the frequency of its occurrence in all samples (number of samples containing the congener/total number of samples).…”

Long-term effects of di-octyl phthalate on the expression of immune-related genes in Tegillarca granosa

“…They are divided into several families, including HSP90, HSP70, HSP60, HSP40, and small HSP (sHSP) according to their molecular size (Mayer, 1997;Santoro, 2000). Stressors, including DOP, that cause oxidative stress also aff ect the expression of HSPs (Wood et al, 1997;Lee et al, 2006). The sHSPs are small stress-induced proteins that function to prevent stress-induced cell damage by binding and maintaining the denatured proteins in a folding-competent state.…”