Effects of pesticide exposure on serum immunoglobulin and complement levels

Immunotoxicity of commercial-mixed glyphosate in broad snouted caiman (Caiman latirostris)

The expansion and intensification of agriculture during the past 50 years is unprecedented, and thus environmental problems have been triggered at different scales. These transformations have caused the loss of habitat and biodiversity, and disruption of the structure and functioning of ecosystems. As a result of the expansion of the agricultural frontier in the recent past, many areas of the natural geographic distribution of the local wildlife, among them crocodilians and particularly the broad snouted caiman (Caiman latirostris), are being exposed to contaminants. The present study was designed to evaluate the effect of commercially-mixed glyphosate (RU) on some parameters of the immune system of C. latirostris. Two groups of caimans were exposed for two months to different concentrations of RU recommended for its application in the field, while one group was maintained as an unexposed control. The RU concentration was progressively decreased through the exposure period to simulate glyphosate degradation in water. After exposure, total and differential white blood cell (WBC), and complement system activity (CS) were determined. In addition, the animals were injected with a solution of lipopolysaccharide (LPS) from Escherichia coli to trigger an immune response and evaluate the parameters associated with it. The results showed that an effect of the herbicide on CS was observed, as animals exposed to RU showed a lower CS activity than animals from the negative control (NC) but not in total WBC. In the case of leukocyte population counts, differences were only found for heterophils and lymphocytes.

Effect of pesticide exposure on immunological, hematological and biochemical parameters in thai orchid farmers- a cross-sectional study

Various studies have found that many Thai orchid farmers used excessive amounts of pesticides without proper protective gear, but no toxicological study has been made. This cross-sectional study aimed to evaluate the immunological, hematological and biochemical statuses of these farmers. Sixty four orchid farmers and 60 controls were studied. Plasma cholinesterase activity, the percentage and absolute number of B lymphocytes (CD19+) were significantly lower in the farmers group (3966.32±1165.48 U/L, 11.61±4.09% and 312.26±164.83 cells/mm3, respectively) as compared to those of controls (5048.85±1139.40 U/L, 14.32±4.23%, 420.34±195.18 cells/mm3, respectively). There was a statistically significant higher level of serum IgE among the orchid farmers (0.031±0.011 mg/dL vs. 0.018±0.007 mg/dL) but not IgG, IgA and IgM, levels. Serum lysozyme level, lymphocyte proliferative responses to mitogens, hematological parameters and kidney function test, were not significantly different between the two groups. The liver function profiles showed significantly lower levels of albumin and serum protein in the farmer group. Thus frequent pesticide exposure resulted in subtle changes of some biological parameters. These changes, though may not be clinically significant, strongly indicated that caution in handing pesticides by these farmers is warranted.

Effects of cypermethrin and methyl parathion mixtures on hormone levels and immune functions in Wistar rats

To study interaction and dose-related effects of mixed cypermethrin and methyl parathion on endocrine and immune functions, 120 Wistar rats were divided randomly into six groups of ten male and ten female rats, respectively, at the age of 2 months. All groups were force-fed every 2 days for 30 days with cypermethrin 0.0, 8.0, 0.0, 8.0, 1.8, 0.4 mg/kg bw and methyl parathion 0.0, 0.0, 0.23, 0.23, 0.0518, 0.0115 mg/kg bw. Controls received vehicle solvent only. Body weight gain and organ weights were measured. Serum or blood were used to test luteinizing hormone, follicle stimulating hormone, estradiol (E(2)), testosterone, thyroid hormones (T(3), T(4), TSH), IgG, IgA, rate of neutrophil phagocytosis and of lymphocyte transformation. The effects on relative weights of ovaries and adrenals, IgA and rate of lymphocyte transformation were antagonistic interaction; the effect on estradiol was synergistic in female, whereas addictive in male rats; and the other indices indicated addictive interaction. Organ weights were similar in exposed and control animals except for adrenal (heavier in exposed rats, P<0.01). Serum levels of FSH and estradiol were higher in exposed groups than in controls (P<0.01). IgG levels were lower in exposed rats than in controls (P<0.01), and IgA levels were higher in exposed females than in controls (P<0.01). Lymphocyte transformation rates were lower (P<0.01) and neutrophil phagocytosis rates were higher (P<0.01) in exposed rats than in controls. Our results showed that exposure to low-dose mixtures of cypermethrin and methyl parathion may affect hormone levels (especially estradiol) and immune function in rats, and the NOAELs of combined compounds were located at 1/600 LD(50).