Life-style and environmental factors in the development of nasal NK/T-cell lymphoma: a case-control study in East Asia

Cases of nasal NK/T-cell lymphoma (NKTCL) occur occasionally in Asian and Latin American countries but rarely in Western countries. The etiological role of life-style and environmental factors in nasal NKTCL was investigated. Five university hospitals in Japan and one each in Korea and China participated in this study; a total of 88 cases and 305 hospital controls were accrued during 2000-2005. The odds ratio (OR) of NKTCL obtained after adjustments of age, sex and country was 4.15 (95% confidence interval (CI), 1.74-9.87) for farmers, 2.81 (CI, 1.49-5.29) for producers of crops, 4.01 (CI, 1.99-8.09) for pesticide users, 11.65 (CI, 1.17-115.82) for residents near garbage burning plants, 2.95 (CI, 1.25-6.95) for former drinkers, and 0.49 (CI, 0.23-1.04) for current smokers. The ORs for crop producers, who minimized their exposure to pesticides by using gloves and glasses, and sprinkling downwind at the time of pesticide use, were 3.30 (95% CI, 1.28-8.54), 1.18 (95% CI, 0.11-12.13) and 2.20 (95% CI, 0.88-5.53), respectively, which were lower than those for producers who did not take these precautions. Exposure to pesticides and chemical solvents could be causative of NKTCL. Taken together, life-style and environmental factors might be risk factors for NKTCL.     

Risk Assessment for Honeybees from Pesticide-Exposed Pollen

A method for assessing the risk for honeybees from pesticide exposure via pollen is proposed. Four pesticides, selected as markers, were monitored in pollen samples collected in two sampling areas, one located in an intensive agricultural area and the other far from direct pesticide impact. Analytical results were consistent with use patterns of the chemicals and their physico-chemical and persistence properties. For a preliminary estimate of bee exposure via pollen, both by ingestion and by contact, an exposure index was developed, based on physico-chemical properties, persistence and application rates. On the basis of the exposure estimates and acute toxicological data (ingestion and contact LD₅₀), Toxicity Exposure Ratios (TERs) were calculated as indicators of the risk for honeybees due to this particular exposure route. TER values were compared to Hazard Quotient (HQ), calculated as the ratio between application rate and the LC₅₀ value, according to European guidelines, showing a satisfactory agreement. The advantage of the above described procedures is that the environmental fate of the chemicals, and not only application rates, are taken into account. This approach may represent a preliminary tool for a comparative screening of the risk for pollinator insects due to this particular exposure route.     

抢救急性有机磷中毒中间综合征的护理体会

目的：总结急性有机磷中毒中间综合征的护理体会。方法：收集不同时间段急性有机磷中毒中间综合征患者的病例资料，观察组11例行系统化整体护理，对照组12例行传统中毒后护理，比较两组护理效果。结果：观察组护理效果明显好于对照组，差异有统计学意义（P〈0．05）。结论：系统化整体护理可使患者在心理和躯体等各方面得到最大限度的受益，值得推广应用。     

Pregnancy Outcomes among Farming Households of Nueva Ecija with Conventional Pesticide Use versus Integrated Pest Management

Abstract

A retrospective cohort study was conducted to compare pregnancy outcomes in farming households that used pesticides conventionally with those that practiced integrated pest management (IPM) in Nueva Ecija, Philippines, in the period 1998–1999. Conventional pesticide users (CPUs) were defined as pesticide appliers who used pesticides routinely and regularly, whereas users of IPM were those who used pesticides as necessary, and on economically injured crop areas only. The data sets were subjected to the chi-square test of association, Fisher's exact probability test, and logistic regression analysis. At a significance level at 0.05, spontaneous abortion occurred significantly more often among the 345 CPU households than among the 331 IPM households (adjusted risk ratio 6.17). Likewise, birth defects were significantly more common in the CPU group (adjusted risk ratio 4.56). Thus, people of reproductive age who plan to have children should avoid any use of pesticides.     

Rating Systems for Pesticide Risk Classification on Different Ecosystems

A novel approach is proposed to quantitatively assess the environmental risks associated with the use of plant protection products. Different ranking indexes for the classification of pesticide risk in various environmental systems at different time and space scales have been developed: PRIHS-1 and PRIHS-2 (Pesticide Risk Index for Hypogean Soil Systems), PRIES-1 and PRIES-2 (Pesticide Risk Index for Epygean Soil Systems), and PRISW-1 and PRISW-2 (Pesticide Risk Index for Surface Water Systems). Such indexes identify the risk for each environmental system immediately after a pesticide spraying (PRIHS-1, PRIES-1, and PRISW-1) or in a wider time--space scale scenario (PRIHS-2, PRIES-2, and PRISW-2). Moreover, a general index (ERIP: Environmental Risk Index of Pesticides) was developed for quantifying the comprehensive risk for the environment. The indexes were calibrated by applying to a large number of pesticides for which data were available. The results of the different indexes are compared and the value and limitations of the approach are discussed.     

Effects of the herbicide alachlor on soil microbial activities

A study was made of the effects of one selected acetanilide herbicide, alachlor, at concentrations of 2.0–10.0 kg ha^–1 on bacterial populations, fungi, dinitrogen fixation bacteria, denitrifying bacteria, nitrifying bacteria, nitrogenase activity, acid and alkaline phosphatases, arylsulfatase and deshydrogenase. The presence of 2.0–10.0 kg ha^–1 of alachlor in the soil increased the total number of bacteria and fungi. The population of denitrifying bacteria increased significantly at concentrations of 5.0–10.0 kg ha^–1. However, aerobic dinitrogen fixing bacteria and nitrogenase activity decreased at alachlor concentrations of 3.5–10.0 kg ha^–1. Acid and alkaline phosphatases, arylsulfatase and dehydrogenase activity decreased significantly initially at concentrations of 5.0–10.0 kg ha^–1, but recovered to levels similar to those in the control. Nitrifying bacteria were not affected as a consequence of the addition of the herbicide to agricultural soil.     

Neuronal Differentiation in PC12 Cells Is Inhibited by Chlorpyrifos and Its Metabolites: Is Acetylcholinesterase Inhibition the Site of Action?

Developmental expression of AChE has been associated with neuronal differentiation (P. G. Layer and E. Willbold, Prog. Histochem. Cytochem. 29, 1-94, 1995). In this study we used pheochromocytoma (PC12) cells, a noncholinergic cell line, rich in acetylcholinesterase (AChE) activity, to examine the effects of cholinesterase-inhibiting pesticides on neural differentiation. The experimental paradigm was focused on whether alterations in cholinesterase (ChE) activity by a pesticide or its metabolites would affect neurite outgrowth, a morphological marker of neuronal differentiation. Results indicated that (1) in controls, both total ChE and AChE activities were significantly increased in NGF-primed PC12 cells compared to NGF-unprimed cells, while the basal expression of butyrylcholinesterase (BuChE) activity was much lower (1.3-7% of total ChE activity) in either the presence or the absence of NGF; (2) an increase in AChE activity was highly correlated (r(2) = 0.99) with the extension of neurite outgrowth, suggesting a link between the expression of AChE activity and the elaboration of neurite outgrowth; (3) NGF increased neurite outgrowth in a time- and concentration-dependent manner; and (4) either chlorpyrifos (CPF) or its metabolites (CPF oxon and TCP) inhibited NGF-induced neurite outgrowth (branches per cell, fragments per cell, total neurite outgrowth per cell) in PC12 cells. These data suggest that the expression of AChE activity is associated with the extension of neurite outgrowth. Both enzyme activity and neurite branching were disrupted by CPF oxon; however, CPF and its other metabolite TCP (1 microgram/ml) caused inhibition of neurite outgrowth in the absence of ChE inhibition, suggesting an alternative mechanism(s) may be involved in pesticide-induced inhibition of differentiation.     

不同剂量的敌枯双对妊娠大白鼠骨髓细胞染色体的畸变作用

将实验孕鼠随机分为5组,供实验的4个组于第7～18d 分别每天口服1.00、0.10、0.05及0.01mg/kg 敌枯双;对照组口服0.5%羧甲基纤维素钠。于孕20d 处死,取骨髓按常规细胞培养、镜检,发现各实验组的细胞畸变率均比对照组高,有高度显著性或显著性。说明其阈剂量在0.01mg/kg 以下,为一强的诱变剂。畸变的类型主要有断片、断裂、微粒、粉碎及多倍体等。     

Critical issues for agrichemical safety in South Africa

A review is made of the potential for environmental and occupational exposure to agrichemicals in South Africa. Data from the farming industry in the Western and Southern Cape regions of South Africa confirm substantial use of a range of insecticides, fungicides, and other agrichemicals. The potential for worker exposure to hazardous agrichemicals is also substantial but, to date, such exposures have been poorly characterized. Further data identify important deficiencies in industrial hygiene measures with regard to safekeeping of chemicals on farms, disposal of empty containers, use of protective equipment, and levels of safety training among farm workers. Evidence is presented for widespread underreporting of agrichemical morbidity and mortality. Surveys investigating acute health effects among farm workers with occupational exposure to agrichemicals in South Africa have produced conflicting results. The possibility of chronic health sequelae from low-dose long-term exposure is an underresearched area that is only now being investigated. A number of important obstacles to agrichemical safety are identified: the multiplicity of laws relating to pesticides administered by different departments resulting in poor coordination; the failure of existing occupational health legislation to address the agricultural workplace adequately; the unavailability and incoordination of safety training; the absence of adequate surveillance data; and inadequacies in statutory requirements with regard to waste disposal on farms. Drawing on experiences of local initiatives, possible solutions are identified that address the public health context of the problem.     

Occupational exposure to endocrine disruptors and lymphoma risk in a multi-centric European study

Background:

Incidence rates of lymphoma are usually higher in men than in women, and oestrogens may protect against lymphoma.

Methods:

We evaluated occupational exposure to endocrine disrupting chemicals (EDCs) among 2457 controls and 2178 incident lymphoma cases and subtypes from the European Epilymph study.

Results:

Over 30 years of exposure to EDCs compared to no exposure was associated with a 24% increased risk of mature B-cell neoplasms (P-trend=0.02). Associations were observed among men, but not women.

Conclusions:

Prolonged occupational exposure to endocrine disruptors seems to be moderately associated with some lymphoma subtypes.