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A novel formulation of cypermethrin was applied as a bath treatment to Atlantic salmon infested with sea lice on a commercial fish farm on the Isle of Skye, Scotland. Twenty 15 m x 15 m cages were treated with cypermethrin at a concentration of 5 micrograms/litre sea water. The numbers of sea lice of all stages were recorded on five fish per cage before the treatment and one, seven and 16 days after treatment. Statistically significant reductions in the numbers of chalimus III and IV pre-adults and adults were recorded over the whole period; the average percentage reductions at one and 16 days after treatment were 59 per cent and 90 per cent (chalimus III and IV), 98 per cent and 95 per cent (pre-adults), and 99 per cent (adults), respectively.

The chemically diþ erent adjuvants 'Agral', 'Bond', 'Codacide Oil', Li 700, 'Silwet L'-77, and 'Headland Guard' were assayed to determine their eþ ects on the rainfastness of an emulsiüable concentrate formulation of the organophosphorus pesticide chlorpyrifos. Cabbage leaves were each treated with 200 Â 0.25-ll droplets of diluted formulation using a hand-held microapplicator. Droplet deposits were left to air-dry for 1 h prior to exposure to simulated rainfall. Rain fastness was assessed using GC residue analyses of treated leaves after exposure to 10, 20 or 30 min simulated rainfall. The results indicated that the latex-based adjuvants 'Bond' and 'Headland Guard' induced a statistically signiücant increase in rainfastness, results for the other adjuvants assayed being either not signiücant or inconclusive. The results are discussed within the context of using adjuvants to enhance insecticide efficacy.

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This study assessed the significance and potential impact of potentially toxic element (PTE) (i.e., Mn, Pb, Cu, Zn, Cr, Cd, and Ni) pollution in the surface soil from an abandoned manganese mining area in Xiangtan City, Hunan Province, China, on the health of residents. The risks were sequentially evaluated using a series of protocols including: the geo-accumulation index (Igeo), pollution load index (PLI), potential ecological risk index (RI), and implications for human health from external exposures using the hazard quotient (HQ), hazard index (HI) and carcinogenic risk (CR). The results revealed that Mn and Cd were the major pollutants in the soil samples. The ecological risk assessment identified moderate risks, which were mainly derived from Cd (82.91%). The results of the health risk assessment revealed that generally across the area, the non-carcinogenic risk was insignificant, and the carcinogenic risk was at an acceptable level. However, due to local spatial fluctuation, some of the sites presented a non-carcinogenic risk to children. The soil ingestion pathway is the main route of exposure through both non-carcinogenic and carcinogenic risks, with Mn being the major contributor to non-carcinogenic risk, with Cr and Cd the major contributors to carcinogenic risk. In addition, three pollution sources were identified through the Pearson correlation coefficient and principal component analysis (PCA), which included: a. mining activities and emissions from related transportation; b. natural background; c. agricultural management practices and municipal sewage discharge. The study provides information on the effects of spatial variation for the development of the abandoned mining areas and a useful approach to the prioritization of locations for the development and utilization of soil in these areas in China.