Determination of four metabolites of the plasticizer di (2-ethylhexyl) phthalate in human urine samples

Summary A method for biological monitoring of exposure to the plasticizer di(2-ethylhexyl)phthalate (DEHP) is described. In this method the four main metabolites of DEHP [i.e., mono (2-ethylhexyl) phthalate (MEHP), mono (5-carboxy-2-ethylpentyl)phthalate, mono(2-ethyl-5-oxohexyl)phthalate, and mono(2-ethyl-5-hydroxyhexyl)-phthalate] are determined in urine samples. The procedure includes enzymatic hydrolysis, ether extraction, and derivatization with triethyloxonium tetrafluoroborate. Analysis is performed by gas chromatography electron impact mass spectrometry. The detection limit for all four metabolites is less than 25 g/l urine. The coefficient of variation based on duplicate determinations of urine samples of workers occupationally exposed to DEHP was 16% for MEHP (mean concentration 0.157 mg/l) and 6% -9% for the other three metabolites (mean concentrations 0.130-0.175 mg/1). The method described here was used to study DEHP metabolism in man. Most persons excrete mono(2-ethyl-5-oxohexyl)-phthalate and mono (2-ethyl-5-hydroxyhexyl)phthalate as a (glucuronide) conjugate. Mono (5-carboxy-2-ethyl-pentyl)phthalate is mainly excreted in free form, while for MEHP a large interindividual variation in conjugation status was observed. Of the four metabolites quantified, 52% are products of a ((-l)-hydroxylation reaction of MEHP [i.e., mono (2-ethyl-5-oxohexyl)phthalate and mono (2-ethyl-5-hydroxyhexyl)phthalate], 22% is the product of a -hydroxylation reaction of MEHP [i.e., mono (5-carboxy-2-ethylpentyl)phthalate], and 26% is not oxidized further (i.e., MEHP). A good correlation is obtained when the amount of MEHP -hydroxylation products is compared with the amount of MEHP (-1)hydroxylation products in urine samples. When the internal dose of DEHP has to be established we recommend that the levels of all four metabolites of DEHP be studied in urine samples.     

Species and inter-individual differences in metabolic capacity of di(2-ethylhexyl)phthalate (DEHP) between human and mouse livers

Objectives

This study was conducted to assess inter-species and inter-individual differences in the metabolism of di(2-ethylhexyl)phthalate (DEHP) in humans and mice.

Methods

The activities of four DEHP-metabolizing enzymes [lipase, UDP-glucuronocyltransferase (UGT), alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH)] were measured in the livers of 38 human subjects of various ages and in eight 129/Sv male mice.

Results

Microsomal lipase activity was significantly lower in humans than in mice. The V _max/K _m value in humans was one-seventh of that in mice, microsomal UGT activity in humans was a sixth of that in mice, and cytosolic ALDH activity for 2-ethylhexanal in humans was one-half of that in mice. In contrast, ADH activity for 2-ethylhexanol was twofold higher in humans than in mice. The total amount of DEHP urinary metabolites and the concentration of mono(2-ethylhexyl)phthalate (MEHP) were much higher in intact mice than in the U.S. general population based on data reported elsewhere, regardless of the similar estimated DEHP intake between these mice and the human reference population. However, mono(2-ethyl-5-oxo-hexyl)phthalate (5oxo-MEHP) and mono(2-ethyl-5-carboxypentyl)phthalate (5cx-MEPP) levels were higher in the latter than in the former. Of note, inter-subject variability in the activities of all enzymes measured was 10–26-fold.

Conclusion

The inter-individual variation in the metabolism of DEHP in humans may be greater than the difference between mice and humans (inter-species variation), and both may affects the risk assessment of DEHP.     

气相色谱-质谱法测定饮用水中19种农药残留及邻苯二甲酸二（2-乙基己基）酯

目的 建立饮用水中19种农药残留及邻苯二甲酸二（2-乙基己基）酯的气相色谱-质谱测定方法。方法 水样用 1∶1正己烷-二氯甲烷混合溶剂萃取、旋蒸浓缩后进样分析。以保留时间、特征离子定性,外标法定量。结果 方法线性范围为0.05～5 mg/L,相关系数为0.9953～0.9998,检出限为0.0009～0.007 mg/L,回收率为86.4%～101.9%,相对标准差为1.8%～8.5%。结论 本方法操作简单、准确快速、灵敏度高、精密度高,满足饮用水中农药和邻苯二甲酸二（2-乙基己基）酯残留的测定要求。     

Internal exposure of nursery-school children and their parents and teachers to di(2-ethylhexyl)phthalate (DEHP)

Di(2-ethylhexyl)phthalate (DEHP) is the main plasticizer for polyvinyl chloride (PVC) products. It has become widely spread in our environment and among people. DEHP is suspected to be responsible for endocrine-disruptor-like effects in mankind. Children are probably most susceptible to these endocrine effects. In this study we determined the internal exposure of nursery school children (aged 2-6 years) to DEHP and compared it to their parents' and teachers' exposure. The DEHP-metabolites mono(2-ethyl-5-hydroxyhexyl)phthalate (5OH-MEHP), mono(2-ethyl-5-oxo-hexyl)phthalate (5oxo-MEHP) and mono(2-ethylhexyl)phthalate (MEHP) were determined in first morning urine. The sum of the three DEHP metabolites in children's and in adults' urine was 90.0 and 59.1 micrograms/l respectively (median values; p = 0.074). Concentrations of the secondary metabolites 5OH-MEHP (median: 49.6 vs. 32.1 micrograms/l; p = 0.038) and 5oxo-MEHP (median: 33.8 vs. 19.6 micrograms/l; p = 0.015) were significantly higher in children than in adults. MEHP concentrations were low both in adults and children (median: 6.6 micrograms/l vs. 9.0 micrograms/l). Creatinine adjusted values should more accurately reflect the dose taken up with respect to body weight when comparing children with adults. Total creatinine adjusted DEHP metabolites in urine were significantly higher in children than in adults (median values: 98.8 vs. 50.9 micrograms/g creatinine; p < 0.0001). This also applied to the concentrations of both secondary metabolites 5OH-MEHP (55.8 vs. 28.1 micrograms/g creatinine; p < 0.0001) and 5oxo-MEHP (38.3 vs. 17.2 micrograms/g creatinine; p < 0.0001). Creatinine corrected concentrations for the monoester MEHP in children and adults were very similar (8.7 vs. 8.6 micrograms/g creatinine; p = 0.908). Based on the sum of the three determined metabolites we estimated the DEHP dose (in microgram/kg body-weight) taken up by children to be about twice as high as the dose taken up by adults. Routes of the ubiquitous exposure to DEHP remain indistinct. In children's urine the mean relative ratios of MEHP to 5OH-MEHP to 5oxo-MEHP were 1 to 7.1 to 4.9, in adults they were 1 to 3.4 to 2.1. This might indicate an enhanced oxidative metabolism in children. To date no information on the biological activity and toxicity of oxidative metabolites of DEHP is available. Since these are the major metabolites of DEHP toxicological data on these metabolites is urgently needed.     

塑料拆解地区水环境中DEHP检测

目的 监测某塑料拆解地区水环境中邻苯二甲酸二(2-乙基己基)酯(DEHP)的污染水平及探讨其可能的来源,为保护当地环境、促进居民健康提供基础数据。方法 用固相萃取和气相色谱联用技术检测河水、井水、塘水、无组织排放水和饮用水中DEHP水平。结果 各类水样中均检出DEHP,检出率为100%。河流污染断面DEHP平均浓度2.05μg/L,为清洁断面平均浓度(0.32μg/L)的6.4倍。暴露区井水(14.20μg/L)和塘水(135.68μg/L)DEHP的平均浓度分别为对照组井水(0.79μg/L)和塘水(0.37μg/L)的18和367倍。暴露区无组织排放水样中DE-HP的检出范围在0.36~161.86μg/L。结论 塑料拆解地区井水、塘水和无组织排放水样中均检出DEHP,且DEHP的平均浓度均超过中国《生活饮用水卫生标准》(GB5479-2006)和《地表水环境质量标准》(GB3838-2002)的要求,应引起重视。     

Prenatal maternal blood triglyceride and fatty acid levels in relation to exposure to di(2-ethylhexyl)phthalate: a cross-sectional study

Objectives

The hypolipidemic effects of di(2-ethylhexyl)phthalate (DEHP) exposure in humans have not been investigated. And the influences of maternal prenatal DEHP exposure on birth outcomes are not well-known. We aimed to estimate prenatal DEHP exposure in maternal blood, and evaluate its relationships to maternal blood triglyceride (TG) and fatty acid (FA) levels and to birth outcomes.

Methods

We studied 318 mother–newborn pairs residing in Sapporo, Japan. Blood was taken one time during pregnancy for each mother. Maternal and infant characteristics were obtained from medical records and questionnaire survey. We measured DEHP metabolite, mono(2-ethylhexyl) phthalate (MEHP), along with TG and 9 FAs using maternal blood, and analyzed associations of MEHP level with maternal blood TG/FA levels and infant birth dimensions.

Results

Maternal blood TG and palmitoleic/oleic acid levels were higher, but stearic/docosahexaenoic acids and MEHP were lower during late pregnancy. Maternal blood MEHP levels inversely correlated with TG and palmitic/palmitoleic/oleic/linoleic/α-linolenic acids. After adjustment for confounders, we found that a tenfold increase in blood MEHP levels correlated with a decrease in TG of 25.1 mg/dl [95 % confidence interval (CI) 4.8–45.3 mg/dl], and similar relations in palmitic (β = −581.8; 95 % CI −906.5, −257.0), oleic (β = −304.2; 95 % CI −518.0, −90.5), linoleic (β = −348.6; 95 % CI −510.6, −186.6), and α-linolenic (β = −6.3; 95 % CI −9.5, −3.0) acids. However, we observed no correlations between maternal blood MEHP levels and infant birth weight, length, chest circumference, or head circumference.

Conclusions

Ambient DEHP exposure during pregnancy inversely correlated with maternal blood TG and 4 FA levels, but not birth outcomes.     

高效液相色谱法测定化妆品中邻苯二甲酸二丁酯和邻苯二甲酸二(2-乙基己基)酯的含量

目的：建立了高效液相色谱法测定化妆品中邻苯二甲酸二丁酯（DBP）和邻苯二甲酸二（2-乙基己基）酯（DE-HP）含量的方法。方法：采用固相萃取法处理样品，淋洗试剂为甲醇：乙醚=1：19。甲醇和水作为流动相，二极管阵列检测器测定DBP和DEHP。结果：DBP测定的线性范围为5．0～200μg／ml，线性相关系数为0．9993，DEHP测定的线性范围为5．5～220μg／ml，线性相关系数为0．9997。DBP的回收率范围在84％～93％，相对标准偏差为3．2％～4．8％。DE-HP的回收率范围在98％～105％，相对标准偏差为2．8％～4．7％。结论：该方法灵敏度高，结果准确而且稳定。     

邻苯二甲酸(2-乙基己基)酯低剂量暴露对雄性小鼠生殖发育的影响

目的观察邻苯二甲酸(2-乙基己基)酯(DEHP)低剂量暴露对雄性小鼠的生殖发育毒性作用。方法将清洁级ICR小鼠随机分为4个DEHP染毒组(1/120LD50,1/60LD50,1/30LD50,1/15LD50,即250、500、1000、2000mg/kg组),阳性对照组(环磷酰胺,40mg/kg)和阴性对照组(玉米油);DEHP染毒组和阴性对照组灌胃染毒30d,阳性对照组灌胃5d,每天1次。采用一般生殖毒性试验和显性致死突变试验的方法,研究DEHP低剂量暴露对雄性小鼠生殖细胞的损伤作用和生育能力的影响。结果一般生殖毒性试验结果显示,低剂量DEHP染毒雄性小鼠睾丸、附睾重量降低(r睾丸=-0.578,P<0.01;r附睾=-0.661,P<0.01),精子总数减少(r=-0.608,P<0.01),精子畸形率增高(r=0.836,P<0.01),精子活动度降低(P<0.05)。显性致死突变试验研究结果显示,250mg/kgDEHP染毒组小鼠受孕率降低,但与阴性对照组比较,差异无统计学意义(P>0.05);DEHP染毒组子代小鼠平均着床数减少(r=-0.892,P<0.01),与阴性对照组比较,差异均具有统计学意义(P<0.01);平均早期死亡胚胎数随染毒剂量增加而增加(r=0.996,P<0.01),250mg/kg染毒组与阴性对照组比较,差异无统计学意义(P>0.05)。结论DEHP低剂量暴露对雄性小鼠具有生殖毒性作用,可降低小鼠受孕率,使子代小鼠平均着床数减少,平均早期死亡胚胎数增加。     

No immunotoxic effect on T cells with di (2-ethylhexyl) phthalate in male C57BL/6 mice

Objectives To clarify whether di (2-ethylhexyl) phthalate (DEHP) has immunotoxic effects on both the expression of surface molecules (CD3, CD4, CD8 and CD28) on T cells of the thymus and spleen in male C57BL/6 mice. Methods Animals were orally administered a 0.1% or 0.2% DEHP-containing diet for 10 or 20 days. Dietary corn oil was used as the vehicle for DEHP in preparing the diet. Results Significant hepatic hypertrophy was clearly observed in the DEHP-exposed groups, while no atrophy was seen in the thymus or spleen in any treatment groups. In the thymus and spleen, no variation in the proportions of both T cells expressing CD3, CD4 and CD8 was shown with cytometry analysis. The surface expression of CD3, CD4, CD8 and CD28 on both T cells was also invariable in all analyzed stages of thymic differentiation and in the spleen. No effect of DEHP on mitogenesis was shown in the splenic T cells with anin vitro [³H]-thymidine-incorporation technique. Conclusions DEHP is probably not an immunosuppressor, particularly for T cells.     

出生前邻苯二甲酸二(2-乙基己基)酯暴露对子代大鼠血清皮质醇激素水平的影响

目的探讨出生前邻苯二甲酸二(2-乙基己基)酯(DEHP)暴露对大鼠肾上腺功能的潜在干扰作用。方法将32只健康SD孕鼠按体重随机分为溶剂对照组(玉米油)及2、10、50 mg/kg DEHP染毒组,每组8只。自孕14~19 d连续灌胃染毒,每日1次。子代大鼠于出生后第21天断乳,雌雄分笼饲养至70日龄,断头处死,取血及双侧肾上腺,计算肾上腺脏器系数,并采用Luminex液态芯片技术测定血清皮质醇水平。结果成年雌性仔鼠肾上腺脏器系数在各染毒组间有差异,与对照组相比,2 mg/kg染毒组的肾上腺重量及脏器系数较低,差异有统计学意义(P0.05);成年雄性仔鼠肾上腺脏器系数在各染毒组间差异均无统计学意义(P0.05)。与对照组相比,10、50 mg/kg染毒组的成年雌性仔鼠血清皮质醇水平较高,差异有统计学意义(P0.01);而2 mg/kg染毒组与对照组相比无明显差异(P0.05)。与对照组相比,10 mg/kg染毒组的成年雄性仔鼠血清皮质醇水平较高,差异有统计学意义(P0.01);而2、50 mg/kg染毒组与对照组相比无明显差异(P0.05)。结论出生前DEHP暴露可能干扰子代大鼠肾上腺功能。     

Di(2-ethylhexyl)phthalate (DEHP) exposure of voluntary plasma and platelet donors

Each year thousands of healthy volunteers undergo apheresis procedures to donate blood components and safe lives. However, many disposables used in apheresis contain di(2-ethylhexyl)phthalate (DEHP). This way, donors are exposed to DEHP, which is a reproductive and developmental toxicant in animals and a suspected endocrine modulator in humans. We quantified the DEHP exposure of six plasma donors, six discontinuous-flow platelet donors and six continuous-flow platelet donors by determining three specific metabolites in urine (5OH-MEHP: mono(2-ethyl-5-hydroxyhexyl)phthalate; 5oxo-MEHP: mono(2-ethyl-5-oxo-hexyl)phthalate and MEHP: mono(2-ethylhexyl)phthalate). We found maximum concentrations in urine samples after the discontinuous-flow plateletpheresis procedure with 826 microg/l for 5OH-MEHP, 774 microg/l for 5oxo-MEHP and 266 microg/l for MEHP (mean of the six volunteers). Metabolite excretions were found to be significantly (p<0.0001) higher for both plateletpheresis techniques compared to plasmapheresis and controls. Continuous-flow plateletpheresis led to significantly higher (p<0.0001) excretions than discontinuous-flow plateletpheresis. Mean absolute DEHP exposures were 1.2 mg for discontinuous- and 2.1 mg for continuous-flow plateletpheresis. Exposure for plasmapheresis (0.37 mg) was in the range of the controls (0.41 mg). Mean DEHP doses for both plateletpheresis techniques (18.1 and 32.3 microg/kg/day) were close to or exceeded the reference dose (RfD) of the US EPA and tolerable daily intake (TDI) value of the EU on the day of the apheresis. Therefore, margins of safety might be insufficient to protect especially young men and women in their reproductive age from effects on reproductivity. At present, discontinuous-flow devices should be preferred to avert conceivable health risks from plateletpheresis donors. Strategies to avoid DEHP exposure of donors during apheresis need to be developed.     

邻苯二甲酸二乙基己酯致小鼠不同器官细胞 DNA-蛋白质效应研究

目的为了探讨邻苯二甲酸二乙基已酯（DEHP）导致生物机体内不同器官DNA-蛋白质的交联（DPC）作用。方法以采用KCl-SDS沉淀法来检测DEHP体外染毒后昆明纯系小鼠体内肝、脑、睾丸、肺等4个器官的细胞中DNA-蛋白质交联含量。结果当DEHP的浓度为5μM时,小鼠肝细胞的DPC系数与对照组相比没有发生显著的变化;当DEHP的浓度分别升高到10、20、40和80μM时,DPC系数显著上升,且DPC含量与对照组相比有极显著差异;在脑细胞中,当DEHP的浓度分别为5、10μM时,能显著诱导DPC的生成（P〈0．05）,但是,随着DEHP的浓度升高,DPC的含量与对照组相比没有显著性差异;在睾丸的细胞中,当DEHP的浓度为5μM时,小鼠睾丸的细胞DPC系数与对照组相比有显著的升高（P〈0．05）;当DEHP的浓度升高到10、20、40、80μM时,DPC系数显著上升,且DPC含量与对照组相比有极显著差异（P〈0．01）;在肺细胞中,DEHP的浓度为5μM时,就能显著诱导DPC的生成（P〈0．05）。结论DNA-蛋白质交联是一种严重的DNA损伤。DEHP可诱导DNA-蛋白质交联的产生。     

溶剂萃取-GC-MS/MS测定水中邻苯二甲酸二（2-乙基己基）酯

目的 建立简便快速检测生活饮用水及水源水中邻苯二甲酸二（2-乙基己基）酯（DEHP）的GC-MS/MS测定方法。方法 取100.0 mL水,加入2.00 mL正己烷,充分振荡提取,静置分层后,取正己烷层1.00 μL于GC-MS/MS定性定量测定。结果 该方法的检出限为0.000 02 mg/L,相对标准偏差＜3%,回收率在85.0%~103.3%之间。结论 该方法简便快速、准确可靠,适合于水样中DEHP的定量测定。     

邻苯二甲酸二异辛酯增塑聚氯乙烯医疗器械的安全性评价

本文总结了采用邻苯二甲酸二异辛酯(DEHP)增塑聚氯乙烯(PVC)生产的医疗器械的安全性评价结果.在大多数临床使用情况下从PVC医疗器械中释放出DEHP的量不会产生不良反应,但是根据研究资料表明对特殊人群主要是男性胎儿、男性新生儿和青春发育期的男性有潜在的高危风险.     

正常儿童血清中邻苯二甲酸二丁酯和邻苯二甲酸-2-乙基己酯水平的测定

目的检测正常儿童血清中邻苯二甲酸二丁酯(DBP)和邻苯二甲酸-2-乙基己酯(DEHP)水平。方法选择上海市正常儿童作为研究对象,用气相色谱检测其血清中DBP、DEHP含量,作正常儿童血清DBP、DEHP浓度分布,以及DBP、DEHP不同年龄和性别水平分析。结果 310例血样中,110例可检出DBP,118可检出DEHP,全部样品中DBP的浓度范围为未检出～0.98ng/ml,P75为0.68ng/ml,95%上限为0.75ng/ml,男女检出率无差别,检出率在不同年龄组间存在差别。全部样品中DEHP的浓度范围为未检出～0.94ng/ml,P75为0.67ng/ml,95%上限为0.74ng/ml,男女检出率无差别,检出率在不同年龄组间存在差别,婴儿组的检出率明显低于其他组。结论正常儿童的血清DBP、DEHP浓度较低,DBP低于0.75ng/ml,DEHP低于0.74ng/ml。     

邻苯二甲酸二乙基己基酯对大鼠睾丸细胞DNA损伤和睾丸组织氧化应激影响

目的 探讨邻苯二甲酸二乙基己基酯(DEHP)对大鼠睾丸细胞DNA的损伤和睾丸组织氧化应激的作用.方法 雄性Wistar大鼠25只,随机分为5组,每组5只,通过灌胃的方法摄入DEHP,4个染毒组剂量分别为1 500、3 000、4 500、6000mg·kg-1 ·d-1,1个阴性对照组.用单细胞凝胶电泳技术检测大鼠睾丸细胞DNA的损伤,睾丸组织中活性氧(ROS)、丙二醛(MDA)的水平以及睾丸组织中谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)的活力.结果 各染毒组和阴性对照组大鼠睾丸细胞DNA损伤率分别为29.0％、71.0％、89.0％、95.0％和15.0％,各染毒组睾丸细胞DNA损伤程度与对照组比较,差异均有统计学意义(P＜0.05,P＜0.01),且大鼠睾丸细胞DNA损伤率与染毒剂量之间呈剂量-反应关系(r =0.930,P＜0.01);各染毒组大鼠睾丸组织的ROS、MDA的水平均较阴性对照组显著升高(P＜0.05,P＜0.01),而GSH-Px、SOD的活力又较阴性对照组明显下降(P＜0.05,P＜0.01).结论 DEHP可造成大鼠睾丸组织明显的氧化应激并引起睾丸细胞DNA的损伤.     

青春期前邻苯二甲酸二(2-乙基)己酯暴露对雌性大鼠生殖发育及过氧化物酶体增殖剂激活受体的影响

目的探讨邻苯二甲酸二(2-乙基)己酯(DEHP)暴露对青春期前雌性大鼠性发育及生殖内分泌功能的影响及其可能机制。方法将40只健康3周龄雌性SD大鼠,随机分成对照组(玉米油)和3个实验组,每组10只。实验组按50、150、500mg/kg DEHP经口灌胃,连续染毒28天。观察阴道开口、乳房发育、第一次发情周期的日龄及体重,于末次染毒24小时后进行阴道涂片,确定动情间期,处死动物。Real-time PCR测定卵巢组织相关基因表达水平;ELISA法检测血清中卵泡刺激素(FSH)、黄体生成素(LH)、雌二醇(E2)、孕酮(P4)及睾酮(T)水平;通过病理学观察卵巢组织的变化;免疫组织化学法测定卵巢组织中PPARγ的表达。结果 500mg/kg组阴道开口日龄提前,150、500mg/kg组阴道开口时体重增加(P<0.05);150、500mg/kg组芳香化酶(P450Arom)mRNA表达与对照组比较,显著下降;各剂量组与对照组相比,T水平明显下降,150、500mg/kg组FSH、E2水平明显减少,而LH水平明显升高(P<0.05);150、500mg/kg组闭锁卵泡明显增多、黄体数目明显减少;150、500mg/kg组卵泡颗粒细胞和黄体颗粒细胞中PPARγ阳性光密度相对量明显高于对照组及50mg/kg组(P<0.05)。结论青春期前DEHP暴露对雌性大鼠性发育及生殖内分泌功能产生影响,其作用机制可能与激活PPARs有关。     

邻苯二甲酸二(2-乙基己基)酯、氯氰菊酯单独及联合染毒对青春前期雄性大鼠生殖发育的不良影响

目的探讨邻苯二甲酸二(2-乙基己基)酯(DEHP)和氯氰菊酯(CYP)单独及联合染毒对青春前期雄性大鼠生殖发育的不良影响。方法选择SPF级3周龄雄性SD大鼠24只,随机分为4组,分别为对照组(喂饲玉米油)、DEHP染毒组(500mg/kg)、CYP染毒组(80mg/kg);DEHP、CYP联合染毒组(DEHP 500mg/kg+CYP 80mg/kg),每组6只。采用经口灌胃方式染毒,每天1次,连续染毒30天。于末次染毒24小时后处死动物,测定大鼠体重、睾丸湿重,并计算睾丸系数;测定血清睾酮水平;制备睾丸病理组织切片,光镜观察其组织学改变,电镜观察生殖细胞超微结构;测定睾丸标志酶乳酸脱氢酶(LDH)、酸性磷酸酶(ACP)、碱性磷酸酶(ALP)和琥珀酸脱氢酶(SDH)的活性。结果与对照组相比,DEHP、CYP单独及联合染毒组睾丸下降时间和包皮分离时间明显延迟,肛门生殖器间距明显缩短(P<0.05或0.01);DEHP单独染毒组睾丸重量及睾丸系数明显降低,血清睾酮水平显著下降(P<0.05),睾丸匀浆中ALP、ACP和LDH活性明显增高,SDH活性显著下降(P<0.01);DEHP、CYP单独及联合染毒组睾丸病理组织学、生殖细胞超微结构均可见明显异常。结论 DEHP、CYP单独及联合染毒对青春前期雄性大鼠均具有明显的生殖毒性作用,可引起生精细胞、支持细胞和间质细胞的变性、坏死及功能障碍,从而导致雄性生殖系统发育和功能的显著异常。其中,DEHP单独染毒呈现主效应,DEHP、CYP联合染毒对大鼠的生殖毒性未呈现明显交互影响。     

邻苯二甲酸二(2-乙基己基)酯对青春前期雄性大鼠的生殖毒性

目的探讨邻苯二甲酸二(2-乙基己)酯(di-2-ethylhexyl phthalate,DEHP)对青春前期雄性大鼠的生殖毒性。方法将32只健康21日龄清洁级雄性SD大鼠按体重随机分为4组,分别为溶剂对照(玉米油)组和250、500、1 000 mg/kg DEHP染毒组,每组8只。采用灌胃方式进行染毒,染毒容量为10 ml/kg,每天1次,连续染毒4周。采用CASA精子分析系统分析精子活力相关指标。结果与对照组比较,1 000 mg/kg DEHP染毒组大鼠的精子密度、精子活动率、活动精子密度、最大侧摆幅度、直线运动的精子密度及A级精子百分率均较低,而D级精子百分率较高;250 mg/kg DEHP染毒组平均直线运动速度、精子运动的向前性均较低;500、1 000 mg/kg DEHP染毒组直线运动的精子个数均较低,差异均有统计学意义(P0.05);而各剂量DEHP染毒组B、C级精子比例和平均曲线运动速度、平均路径速度、平均侧摆幅度、平均鞭打频率、运动的直线性、运动的摆动性、平均移动角度、直线运动精子活率均无明显改变。结论 DEHP对青春前期雄性大鼠精子活力产生明显的毒性作用,从而影响雄性的生殖功能。     

不同烹调油样品中邻苯二甲酸二丁酯与邻苯二甲酸二（2-乙基己基）酯的分析

[目的]了解不同烹调油样品中邻苯二甲酸二丁酯（di-n—butyl phthalate,DBP）与邻苯二甲酸二（2-乙基己基）酯[di（2-ethylhexyl）phthalate,DEHP]的污染情况。[方法]采用气相色谱-质谱联用仪的选择离子检测（SIR）方式,测定取自居民家中未加热食用油、烹调剩油和厨房抽油烟机内油盒中的烹调油烟冷凝物,食堂中未加热食用油、烹调剩油和烹调油烟冷凝物;小摊贩所用的未加热食用油及其锅内剩油;快餐店未加热过的固体起酥油及烹调剩油等样品中DBP与DEHP的含量。[结果]9户居民家庭厨房和食堂不同烹调油样品中DBP和DEHP均为阳性,且烹调油烟冷凝物中的含量明显高于未加热食用油和烹调剩油中的含量;DBP和DEHP含量：前者分别为2．29～597．01μg／g和38．96～4774．72μg／g;后者分别为3．22～42．81μg／g和15．61～112．64μg／g。小摊贩和快餐店不同烹调油样品中,仅1例炸面食剩油检出DBP和DEHP。[结论]大部分烹调油样品被DBP、DEHP污染,且烹调油烟冷凝物中的含量大大增加。