Effects of pentachlorophenol on Galba pervia, Tubifex sinicus and Chironomus plumousus larvae

Transcriptional changes induced by in vivo exposure to pentachlorophenol (PCP) in Chironomus riparius (Diptera) aquatic larvae

Pentachlorophenol (PCP) has been extensively used worldwide as a pesticide and biocide and is frequently detected in the aquatic environment. In the present work, the toxicity of PCP was investigated in Chironomus riparius aquatic larvae. The effects following short- and long-term exposures were evaluated at the molecular level by analyzing changes in the transcriptional profile of different endocrine genes, as well as in genes involved in the stress response and detoxification. Interestingly, although no differences were found after 12- and 24-h treatments, at 96-h exposures PCP was able to induce significant increases in transcripts from the ecdysone receptor gene (EcR), the early ecdysone-inducible E74 gene, the estrogen-related receptor gene (ERR), the Hsp70 gene and the CYP4G gene. In contrast, the Hsp27 gene appeared to be downregulated, while the ultraspiracle gene (usp) (insect ortholog of the retinoid X receptor) was not altered in any of the conditions assayed. Moreover, Glutathione-S-Transferase (GST) activity was not affected. The results obtained show the ability of PCP to modulate transcription of different biomarker genes from important cellular metabolic activities, which could be useful in genomic approaches to monitoring. In particular, the significant upregulation of hormonal genes represents the first evidence at the genomic level of the potential endocrine disruptive effects of PCP on aquatic invertebrates.

Pentachlorophenol removal from aqueous solutions by microwave/persulfate and microwave/H2O2: a comparative kinetic study

Pentachlorophenol (PCP) is one of the most fungicides and pesticides used in wood protection. Poisoning from PCP may be happened in dermal absorption, and respiration or ingestion. With regard to health and environmental effects of PCP, many methods were studied for its removal. Microwave assisted other methods are environmental friendly, safety, and economical method, therefore, in this study; a modified domestic microwave assisted hydrogen peroxide (MW/H2O2) and sodium persulfate (MW/SPS) was used for PCP removal from aqueous solutions. PCP removal rate was measured under different factors such as pH, energy intensity, SPS, H2O2 concentration, Tert- butyl alcohol (TBA) and chemical oxygen demand (COD). The concentration changes of PCP were determined using spectrophotometer and HPLC spectra, respectively. The best removal PCP rate obtained in condition of pH of 11, 0.02 mol L(-1) of SPS, 0.2 mol L(-1) of H2O2 and energy intensity of 600 W. Moreover, COD removals in MW/H2O2 and MW/SPS process were 83% and 94%, respectively, also TBA test decreased 15% and 3% of PCP removal in MW/SPS and MW/H2O2 processes respectively. Experimental results indicated that sulfate radical was stronger than hydroxyl radical and examinations order reaction was in first order. In this study, was cleared that MW/SPS process was more effective than MW/H2O2 process in PCP removal.