Alterations in some physiological processes of Bactrocera oleae Rossi (Diptera: Tephritidae) following pyridalyl treatment.

Pyridalyl is one of the recently discovered insecticides which has shown toxicity against several insect pests with slight- or non-lethal effects against natural enemies. Cytotoxicity and prevention of protein synthesis have been reported as pyridalyl mode of action. In the current study, adults of Bacterocera oleae, as a major pest of olive, were fed on protein hydrolysate diet containing LC50 concentration of pyridalyl to determine the possible mode of action through gene expression and amino acid profile. Results showed that treated flies had significantly higher gene expressions of cytochrome P450, insulin receptor-like, antioxidant enzymes (catalase, peroxidase, superoxide dismutase) and the enzymes involved in cell death; caspase1, caspase3, caspase8 and caspase9 compared to control. Moreover, determination of amino acid profile in the whole body of both control and pyridalyl-treated B. oleae revealed the significant higher amounts of glutamic acid, glutamine, histidine, threonine, citrulin, arginine, taurine, alanine, tyrosine, α-amino butric acid, methionine and isoleucine in the treated adults while the control flies had the higher amounts of serine, glycine and tryptophane. No significant differences were found in the amounts of asparagine and phenylalanine between control and treatments. These results are in accordance with earlier findings on mode of action of pyridalyl through activation of cytochrome P450 system and alterations in protein synthesis machinery although here other mechanisms were also reported including activation of insulin receptor and antioxidant enzymes. Moreover, it is the first report on cytotoxicity through apoptosis with engagement of caspases.

Persistent organic pollutants in muscle and feather of ten avian species from Mazandaran Province of Iran, on the coast of the Caspian Sea.

Feather and muscle of 10 avian species (n = 46), were analyzed for polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). Muscle contained significantly higher PCB and OCP than liver and feather. Mean muscle and feather PCB was 408.5 ± 134.5 and 32 ± 4.5 ng/g wet weight. Highly chlorinated PCBs were found in muscle and liver while feather had PCBs with less chlorination. Gulls had highest levels of both pollutants. Gull feather PCB and OCP were strongly correlated with their levels in the liver and muscle tissues (0.6 < r < 0.9, p < 0.01). Analysis of gull feather can be used as a non-invasive method for monitoring organic pollutants.

Mercury concentration in 3 species of Gulls, Larus ridibundus, Larus minutus, Larus canus, from south coast of the Caspian Sea, Iran.

In this study, the mercury concentrations of liver, breast feathers and tail feathers in three species of Gull; Black-headed Gull (Larus ridibundus), Common Gull (Larus canus) and Little Gull (Larus minutus) from the South coast of the Caspian Sea in Iran were assayed. Mercury accumulation in liver, breast feathers and tail feathers of species were 1.69-3.16, 2.88-7.18 and 2.09-5.66 mg/kg, respectively. Mercury concentration hierarchy in tissues we tested was as follows: breast feather > tail feather > and liver. We found that despite its small size, Little Gull had highest (3.85-8.05 mg/kg) and Common Gull lowest (1.69-2.88 mg/kg) level of Hg in their bodies. An inverse relationship between body size and Hg levels in these Gulls was detected. Mercury in Little Gull and Black-headed Gull exceeded the 5 ppm threshold for adverse effect.

PCBs and organochlorine pesticides in ducks of Fereydoon-kenar wildlife refuge in Iran.

Levels of organochlorine pesticides (OCPs) and PCB were determined in three duck species: Pintail (Anas acuta), Common Teal (Anas creaca), and Mallard (Anas platyhynchos). Both persistent organochlorines were more abundant in muscle than in the liver; Mallard had the highest levels of PCBs [84.0 +/- 39.0 ng/g wet weight (ww)], and Common Teal showed the highest levels of DDTs (561.0 +/- 220.0 ng/g ww). This exposure level is more than two orders of magnitude below provisional tolerable daily intake (PTDI) (0.01 mg/kg bw for DDT and its associated compounds) of The Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO).

Avian liver organochlorine and PCB from South coast of the Caspian Sea, Iran.

Liver samples (n = 43) of 9 avian species representing the families Phalacrocoracidae, Podicipedidae, Laridae, and Anatidae, were collected from the Iranian coast of the Caspian Sea. Samples were analyzed for organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), and seven PCB congeners. p,p'-DDE was predominantly found in all species, at concentrations ranging from the limit of quantification (LOQ) to 340 ng/g ww. Most frequently encountered PCB congeners, in all samples, were 118, 153 and 138; and birds in Phalacrocoracidae had the highest liver PCB (mean 90 +/- 32; ranging from