Effects of accumulated dietary Kepone on spot (Leiostomus xanthurus)

Juvenile spot were administered Kepone^® (chlordecone) by ingestion. Body burdens of Kepone increased additively and equilibrium was not attained. When spot were fed a lethal concentration (3.3 μg/g) over 28 days, they accumulated an average of 2.7 μg/g (wet wt). Most of them developed muscular tetany, fractured vertebral centra, and abnormally thickened vertebrae. These symptoms developed over a 4-wk period until death. Spot fed lesser concentrations (0.59 and 0.30 μg/g) accumulated 0.7 and 0.3 μg/g over 56 days and developed similar bone damage. The percentage of collagen in vertebrae was significantly greater in the treated fish which had thickened bones. Spot that were held in the laboratory as controls for 5 wk had significantly lower collagen percentages than wild fish. These results confirm Kepone accumulation as the likely mechanism for production of the bone deformities observed in fishes from the James River in 1971–1976.     

Can exposure characterization explain concurrence or discordance between toxicology and epidemiology?

The importance of reliable exposure assessment, as a key component of the overall risk assessment process, has been well described for some considerable time. Yet, despite this widely accepted tenet, many studies conclude significant adverse health effects, with associated public policy implications, in the absence of adequate or, in some cases, even rudimentary, exposure quantification. Moreover, it appears that epidemiological studies in humans and toxicological studies in experimental animals may both suffer from inadequate exposure assessment. In this review, we discuss the nature and quality of the exposure assessment in both epidemiologic and toxicologic studies using examples from the pesticides and phthalate literature. Each type of study has its strengths and weaknesses in how exposure is assessed and often the strength of one is also a weakness. It would appear that insufficient or incomplete information about differences in exposure assessment could explain, at least in some cases, the differences in outcome between toxicological and epidemiological studies. Research efforts should focus on improving the feasibility of including biomonitoring in both animal and human studies to facilitate comparisons between animal and human models and improve exposure assessment in epidemiologic studies. Animal and human studies should measure the same biomarkers, where possible, to facilitate human health risk assessment.     

气相色谱-质谱法测定太子参药材中有机氯类农药残留

目的:研究太子参药材中15种有机氯类农药:六六六(包括α-,β-,γ-,δ-BHC)、滴滴涕(包括 p,p′-DDE,p,p′-DDD,p,p′-DDT,o,p′-DDT)、五氯硝基苯、七氯、艾氏剂、硫丹、狄氏剂、异狄氏剂、甲氧氯的毛细管气相色谱-质谱(GC-MS)测定方法。方法:太子参样品经正己烷-丙酮(8:2)振荡提取、Florisil 硅土色谱柱净化处理,用 HP-5MS 弹性石英毛细管柱(30 m×0.25 mm×0.25 μm)经程序升温(初温50℃,以30℃·min~(-1)升至200℃并保持3 min,以30℃·min~(-1)升至230℃并保持3 min,以20℃·min~(-1)升至250℃并保持3 min)技术分离,并用质谱检测器检测。确认含有该种农残的条件:1.可疑色谱峰的定量离子和参比离子提取质量色谱图的保留时间都和标准品一致;2.定量离子和参比离子响应强度的比值和标准品相比相对标准偏差在±15%以内。结果:15种有机氯农药获得了良好的分离,线性关系良好,相关系数为0.9807～0.9963;柃出限为2.0～36 ng·g~(-1);平均加样回收率为70.7%～124%,RSD 为0.9%～11%。所测样品中含有痕量的农药残留。结论:本法简便、准确,净化效果好,可用于太子参药材中15种有机氯农药残留量的检测。     

急性有机磷农药中毒的急救护理

目的探讨急性有机磷农药中毒的急救与护理，及应用解毒剂、复能剂与积极的护理措施是否可提高治愈率。方法回顾性分析134例急性有机磷农药中毒的临床资料。结果134例患者中轻、中度中毒者全部治愈，重度中毒患者死亡6例，抢救成功率95、5％。结论对急性有机磷农药中毒患者进行争分夺秒的抢救与细心护理至关重要，可明显提高治愈率。     

凝胶渗透色谱净化-气相色谱测定中成药中有机氯农药的残留量

目的建立凝胶渗透色谱(GPC)净化-毛细管气相色谱测定中成药中有机氯农药残留量的方法。方法凝胶渗透色谱采用的流动相为丙酮-环己烷(1∶4),最佳流速是5 ml/min,最佳馏分收集时间是15~26 min。结果低、中、高3个添加水平的回收率分别为85.5%~115.0%,84.3%~123.4%,86.7%~114.0%,相对标准偏差(RSD)为0.1%~9.3%,检出限0.008~0.05μg/kg。结论该方法简便,分离效果好,灵敏度高,重现性好。     

人参的质量标准研究

目的：建立人参的质量标准。方法：对人参特征成分进行TLC鉴别及含量测定；测定人参样品中的重金属含量和农药残留量并提出人参中重金属和农残的限量标准。结果：方法简便、可靠、重现性好，平均回收率为98．1％（n=5），RSD=1．52％。结论：本研究可作为人参药材及制品的鉴别，丰富和完善了《中国药典》中人参的质量标准。     

慢性有机磷农药接触对羧基酯酶活力的影响

目的　酯酶不仅在有机磷农药解毒中发挥重要作用 ,而且与心血管疾病有密切关系。我们研究3种酯酶 (丁酰胆碱酯酶BchE、羧酸酯酶CarbE和对氧磷酶PonE)的酶活力在一般人群中的特点 ,探讨有机磷农药慢性接触对酶活力的影响 ,为其他研究提供基线资料。方法　选取 10 0名无有机磷农药接触的对照人群和 75名长期接触有机磷农药的生产工人 ,检测外周血酯酶活力 ,描述正常成人酶活力的特点 ,分析有机磷接触对酯酶活力的影响。结果　对照人群BchE均值为 (78 3± 30 4 )mmol/(ml·h) ;CarbE均值为(36 2 7± 195 0 )nmol/(ml·min) ;PonE均值为 (332 6± 96 2 )nmol/(ml·min)。 3种酶活力在人群中均呈正态分布。有机磷农药接触工人BchE活力为 (2 7 3± 2 1 7)mmol/(ml·h) ;CarbE活力为 (2 35 6± 10 4 0 )nmol/(ml·min) ;PonE活力为 (30 7 8± 10 7 0 )nmol/(ml·min)。结论　 3种酯酶活力无年龄和性别差异。有机磷接触工人的BchE和CarbE活力与对照人群比较 ,差异有显著性 ,说明有机磷能抑制BchE和CarbE活力 ,而对对氧磷酶活力无抑制作用。提示 ,BchE和CarbE活力可以作为反映有机磷农药接触     

Impact of non-functionalized and amino-functionalized multiwall carbon nanotubes on pesticide uptake by lettuce (Lactuca sativa L.)

Abstract

The effect of non-functionalized and amino-functionalized multiwall carbon nanotube (CNT) exposure, as well as the impact of CNT presence on coexistent pesticide accumulation, was investigated in lettuce (Lactuca sativa L.). Lettuce seeds were sown directly into CNT-amended vermiculite (1000?mg?L^?1) to monitor phytotoxicity during germination and growth. During growth, lettuce seedlings were subsequently exposed to chlordane (cis-chlordane [CS], trans-chlordane [TC] and trans-nonachlor [TN]) and p,p′-DDE (all at 100?ng/L) in the irrigation solution for a 19-d growth period. CNT exposure did not significantly influence seed germination (82–96%) or plant growth. Similarly, pesticide exposure had no impact on plant growth, total pigment production or tissue lipid peroxidation. After 19?d, the root content of total chlordane and p,p′-DDE was 390 and 73.8?µg?g^?1, respectively; in plants not exposed to CNTs, the shoot levels were 1.58 and 0.40?µg?g^?1, respectively. The presence and type of CNT significantly influenced pesticide availability to lettuce seedlings. Non-functionalized CNT decreased the root and shoot pesticide content by 88% and 78%, respectively, but amino-functionalized CNT effects were significantly more modest, with decreases of 57% in the roots and 23% in the shoots, respectively. The presence of humic acid completely reversed the reduced accumulation of pesticides induced by amino-functionalized CNT, likely due to strong competition over adsorption sites on the nanomaterial (NM). These findings have implications for food safety and for the use of engineered NMs in agriculture, especially with leafy vegetables.     

Associations of xenobiotic-metabolizing enzyme genotypes PON1Q192R,PON1L55M and CYP1A1*2A MspI with pathological symptoms of a rural population in south Greece

1. Paraoxonases and cytochromes P450 constitute two major classes of xenobiotic-metabolizing enzymes involved in the detoxification of pesticide chemicals. In this study, we examined the distribution of two common genetic polymorphisms of the paraoxonase 1 gene and one common polymorphism of the CYP1A1 gene, in relation to pathological diseases occurring in a rural population.

2. Blood and hair samples were collected from 220 participants of an agricultural cohort in the south of Greece for genotype and pesticide analysis. Demographic information and disease status of the participants was obtained by questionnaire, medical examination and medical record. Organochlorine pesticides and metabolites (DDTs, HCHs) were extracted from hair and analyzed using gas chromatography combined with mass spectrometry techniques.

3. Our results indicate exposure of the rural population of Amaliada to organophosphate and past exposure to organochlorine pesticides.

4. Genotypic analysis of PON1Q192R, PON1L55M and CYP1A1*2A MspI polymorphisms was performed using PCR-RFLP. The PON1 192R and 55M alleles absence was significantly associated with hypertension (OR: 2.59; 95% CI: 1.10–6.09) and hepatitis (OR: 21.43; 95% CI: 2.53–181.50), respectively, as indicated from backward logistic regression. Although the presence of PON1 192R allele significantly affected the occurrence of prostate hyperplasia (OR: 0.35; 95% CI: 0.03–0.40), no associations were obtained between the paraoxonase serum activity or the CYP1A1 genotype and the disease status.

     

急性有机磷中毒的治疗进展

急性有机磷农药中毒（AOPP）是我国常见的中毒性疾病,发病急、变化快、死亡率高。及时而正确的治疗可以提高患者的治愈率,降低死亡率。目前有机磷农药中毒多采用迅速清除毒物、紧急复苏、应用解毒剂、对症处理以及中间综合症的治疗。