Reproductive and Developmental Toxicity of Phthalates

The purposes of this review are to (1) evaluate human and experimental evidence for adverse effects on reproduction and development in humans, produced by exposure to phthalates, and (2) identify knowledge gaps as for future studies. The widespread use of phthalates in consumer products leads to ubiquitous and constant exposure of humans to these chemicals. Phthalates were postulated to produce endocrine-disrupting effects in rodents, where fetal exposure to these compounds was found to induce developmental and reproductive toxicity. The adverse effects observed in rodent models raised concerns as to whether exposure to phthalates represents a potential health risk to humans. At present, di(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP), and butyl benzyl phthalate (BBP) have been demonstrated to produce reproductive and developmental toxicity; thus, this review focuses on these chemicals. For the general population, DEHP exposure is predominantly via food. The average concentrations of phthalates are highest in children and decrease with age. At present, DEHP exposures in the general population appear to be close to the tolerable daily intake (TDI), suggesting that at least some individuals exceed the TDI. In addition, specific high-risk groups exist with internal levels that are several orders of magnitude above average. Urinary metabolites used as biomarkers for the internal levels provide additional means to determine more specifically phthalate exposure levels in both general and high-risk populations. However, exposure data are not consistent and there are indications that secondary metabolites may be more accurate indicators of the internal exposure compared to primary metabolites. The present human toxicity data are not sufficient for evaluating the occurrence of reproductive effects following phthalate exposure in humans, based on existing relevant animal data. This is especially the case for data on female reproductive toxicity, which are scarce. Therefore, future research needs to focus on developmental and reproductive endpoints in humans. It should be noted that phthalates occur in mixtures but most toxicological information is based on single compounds. Thus, it is concluded that it is important to improve the knowledge of toxic interactions among the different chemicals and to develop measures for combined exposure to various groups of phthalates.     

GC-MS法测定药物制剂中邻苯二甲酸酯类化合物的含量

目的建立盐酸雷尼替丁制剂中邻苯二甲酸酯类化合物的检测方法。方法以甲醇为溶剂制备溶液;采用GC-MS法检测,使用DB-5MS色谱柱,载气为氦气,流速为1.0 mL·min-1,检测方式为SCAN和SIR。结果实验条件下,20种邻苯二甲酸酯类化合物能很好分离检测;各组分的检测限（S/N=3）大于2μg·g-1,线性范围在2～40μg·mL-1之间,r〉0.99;加样回收率在79%～99%之间,RSD〈10.8%。结论本法操作简便、准确,分离效果好,对色谱柱和仪器污染小,进样残留少,可同时测定口服固体制剂中的20种邻苯二甲酸酯类化合物。     

A Category Approach for Reproductive Effects of Phthalates

In regulatory toxicology, the experimental assessment of reproductive toxicity is one of the most costly endpoints to perform. Categorizing chemicals is an approach that can be used to reduce animal tests in risk assessments of chemicals, for example, via REACH (Registration, Evaluation, and Authorization of Chemicals). The category approach was tested for reproductive toxicity with a group of 10 ortho-phthalate esters, with different side chain lengths. Three ortho-phthalates were used for testing the category. Phthalates with side-chain lengths C4 to C6 that are commonly known to cause reproductive effects were included, as well as the recently discovered mechanism that indicates antiandrogenic effects. The differences in physicochemical properties, absorption rates, and metabolism between the phthalates investigated could not fully explain the difference in reproductive toxicity. It was concluded that phthalates with the alkyl side-chain length from C4 to C6 produce similar severe reproductive effects in experimental animals. It is expected that phthalates included in the tight boundaries of the proposed category would all show severe reproductive effects, especially the antiandrogenic effects. Further testing might not be needed for phthalates within these boundaries. If necessary, limited testing could focus on the critical endpoints. Detailed mechanistic information is needed on phthalates to apply the categories for regulatory toxicology.     

Phthalates inhibit tamoxifen-induced apoptosis in MCF-7 human breast cancer cells

Environmental estrogens represent a class of compounds that can mimic the function or activity of the endogenous estrogen 17 -estradiol (E2). Phthalates including butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP) are used as plasticizers, and also widely used in food wraps and cosmetic formulations. Phthalates have been shown to mimic estrogen and are capable of binding to the estrogen receptor (ER). It has been demonstrated that estrogen promotes drug resistance to tamoxifen (TAM) in breast cancer. In order to further evaluate the potential role of the phthalates as environmental estrogens, the effect of phthalates was investigated on TAM-induced apoptosis in MCF-7 human breast cancer cells. Our results show that phthalates, BBP (100 M), DBP (10 M), and DEHP (10 M), significantly increased cell proliferation in MCF-7, but not in MDA-MB-231 cells. In addition, BBP, DBP, and DEHP mimicked estrogen in the inhibition of TAM-induced apoptosis in MCF-7 cells. Our data suggest that the inhibitory effect of phthalates on TAM-induced apoptosis involves an increase in intracellular Bcl-2 to Bax ratio. Given that the phthalates are widely used in cosmetics mainly for women, our findings that revealed the promoting effect of BBP, DBP, and DEHP on chemotherapeutic drug resistance to TAM in breast cancer may be of biological relevance.     

UPLC-MS测定薄膜衣片中16种邻苯二甲酸酯类塑化剂

目的 建立UPLC-MS测定薄膜衣片中16种邻苯二甲酸酯类塑化剂含量的方法。方法 采用甲醇提取,Waters ACQUITY UPLC BEH C₁₈色谱柱（2.1 mm×50 mm,1.7 μm）同时串联Waters PFCs Isolator捕集柱（2.1 mm×50 mm）,以0.1%甲酸水溶液和甲醇为流动相,梯度洗脱,流速：0.4 mL·min^-1;采用电喷雾离子源,正离子模式,多反应监测模式检测。结果 在实验条件下,16种塑化剂分离良好;DBP、DIBP检测限为0.5 mg·kg^-1,其余14种塑化剂检测限为0.1 mg·kg^-1;DBP、DIBP在0.20~1.00 μg·mL^-1内,其余14种塑化剂在0.05~1.00 μg·mL^-1内,峰面积与检测浓度之间的线性关系良好（r ≥ 0.995）;平均回收率均在83%~115%之间。结论 该方法操作简单、快速、准确,适用于薄膜衣片中邻苯二甲酸酯类塑化剂的测定。     

毛细管气相色谱法测定邻苯二甲酸二乙酯中16种邻苯二甲酸酯类杂质含量

目的:建立邻苯二甲酸二乙酯中16种邻苯二甲酸酯类杂质的测定方法。方法 :采用毛细管气相色谱法,以(5%)苯基-(95%)甲基聚硅氧烷为固定液,柱温为150℃,保持1 min,以10℃.min-1升温至220℃,再以5℃.min-1升温至300℃,保持6 min;进样口温度为250℃;检测器温度为350℃;载气流量为1℃.min-1;进样量1μL,分流比10:1。以邻苯二甲酸二乙酯为对照品,按标准曲线法以峰面积计算邻苯二甲酸二乙酯中16种邻苯二甲酸酯类杂质的含量。结果 :在选定的色谱条件下,邻苯二甲酸二乙酯与16种邻苯二甲酸酯类杂质分离良好,邻苯二甲酸二乙酯在12.6～126μg.mL-1的范围内线性关系良好,回归方程为Y=0.0271X+0.0007(r=1);16种邻苯二甲酸酯类杂质邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二异丁酯(DIBP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二(2-甲氧基)乙酯(DMEP)、邻苯二甲酸二(4-甲基-2-戊基)酯(BMPP)、邻苯二甲酸二(2-乙氧基)乙酯(DEEP)、邻苯二甲酸二戊酯(DPP)、邻苯二甲酸二己酯(DHP)、邻苯二甲酸丁苄酯(BBP)、邻苯二甲酸二(2-丁氧基)乙酯(DBEP)、邻苯二甲酸二环己酯(DCHP)、邻苯二甲酸二辛酯(DEHP)、邻苯二甲酸二苯酯、邻苯二甲酸二正辛酯(DNOP)、邻苯二甲酸二异壬酯(DINP)、邻苯二甲酸二壬酯(DNP)检出限均在0.25μg.mL-1以下;精密度RSD均在2.0%以下;平均回收率均在82.3%～105.4%范围内。结论:该方法准确、可靠,可用于邻苯二甲酸二乙酯中16种邻苯二甲酸酯类杂质的检测。     

Phthalates and organophosphorus compounds as cholinesterase inhibitors in fractions of industrial hexane impurities

Cholinesterase (ChE) inhibitors have been described in the distillation residue of hexane and other industrial solvents. The residue of a commercial hexane has been fractionated by preparative chromatography. The anticholinesterase (antiChE) activity was isolated in two fractions (F-5, F-7) which contained only 0.61 and 0.16% respectively of the original dry weight hexane residue. In the former fraction, reversible and irreversible progressive inhibition was observed, and organophosphorus compounds (OPs) were detected colorimetrically and by gas chromatography. This fraction was subfractionated in a second chromatographic step. One subfraction containing the highest antiChE activity and 88% phosphorus of F-5 was isolated. In this subfraction triphenylphosphate and other not definitely identified OP compounds were detected by gas chromatography/mass spectrometry, together with several adipates and phthalates, including di-n-butylphthalate. This phthalate could explain the reversible inhibition of ChE by the hexane residue, and triphenylphosphate and the unidentified OP the irreversible inhibition. A possible toxicological role of these impurities is discussed in relation to occupational neuropathies by exposure to solvents.     

GC-MS法测定硫酸庆大霉素滴眼液中17种邻苯二甲酸酯类

目的：建立硫酸庆大霉素滴眼液中17种邻苯二甲酸酯类增塑剂残留量的GC-MS测定方法。方法：采用Agilent HP-5MS气相色谱柱(30 m×0.25 mm,0.25 μm),载气为高纯度氦气(He),进样口温度为260 ℃,脉冲不分流进样,程序升温,进样量为1 μL,离子源为电子轰击源(EI),电离电压为70 eV,离子源温度为300 ℃,质谱传输接口温度为280 ℃,四级杆温度为180 ℃,质谱监测模式为选择离子(SIM)模式,外标法定量。结果：17种邻苯二甲酸酯类增塑剂均在相应的浓度范围内线性关系良好,方法精密度、重复性、回收率、稳定性均符合相关规定。原辅料中检出4种邻苯二甲酸酯类增塑剂,包材中检出6种邻苯二甲酸酯类增塑剂,硫酸庆大霉素滴眼液中检出6种邻苯二甲酸酯类增塑剂。结论：所建立的方法灵敏度高、准确性高、重复性好、速度快,同时提取方法简单,可用于硫酸庆大霉素滴眼液中17种邻苯二甲酸酯类增塑剂迁移情况的监测和溯源。     

GC-MS法检测盐酸雷尼替丁制剂中的20种邻苯二甲酸酯类塑化剂

目的:建立口服固体制剂中邻苯二甲酸酯类塑化剂的检测方法。方法:采用甲醇提取、过滤后进行气相色谱-质谱法分析,对以盐酸雷尼替丁胶囊(片)为模型对象的285批口服固体制剂进行检测。色谱柱为DB-5MS,载气为氦气,流速为1.0ml/min,分流比为10:1,进样口温度为250℃;柱温为程序升温。电子轰击电离方式;电子轰击能为70eV;定性分析采用扫描模式,扫描质量范围为50～650amu;定量测定采用选择离子监测模式。结果:在本试验条件下,20种邻苯二甲酸酯类分离较好,其中18种组分的检测限均>2μg/g,检测质量浓度线性范围均为2～40μg/ml,相关系数均>0.99,RSD均<10%,加样回收率为79%～99%。结论:本法操作简便、准确、分离效果好,可同时检测口服固体制剂中的20种邻苯二甲酸酯类塑化剂。     

Phthalates suppress the calcium signaling of nicotinic acetylcholine receptors in bovine adrenal chromaffin cells

Researchers have recently reported on the nongenomic action of estrogen via membrane receptors and ion channels, especially nicotinic acetylcholine receptors (nAChR). We studied the nongenomic effects of eight phthalates (an endocrine disrupter that expresses estrogen-like activity through estrogen receptors): di-n-ethyl (DEP), di-n-propyl (DPrP), di-n-butyl (DBP), benzyl-n-butyl (BBP), di-n-pentyl (DPP), di-n-hexyl (DHP), dicyclohexyl (DCHP), and di-(2-ethylhexyl) (DEHP). Specifically, we looked at their individual effects on cytosolic free calcium concentration rise induced by three nAChR agonists: carbachol, 1,1-dimethyl-4-phenyl-piperazinium iodide, and epibatidine. Results show that all of the tested phthalates suppressed nAChR-coupled Ca(2+) response. Strongest to weakest potencies were observed as DPP --> BBP --> DBP --> DCHP --> DHP --> DPrP --> DEHP --> DEP. DPP, DBP, and BBP were 10 times more potent than estradiol. We suggest that phthalate potency was associated with its chemical structure, since (a) the most effective phthalates had dialkyl group carbon numbers of C4 or C5, with shorter or longer numbers resulting in decreased potency, and (b) the presence of an alkyl ring or phenoic structure resulted in increasing potency. Because of the similarity between this relationship and estrogen receptor-binding potency, we suggest that the inhibitory effect of phthalates on nAChR-coupled Ca(2+) response is an indication of their nongenomic estrogen-like activity.     

Non-carcinogenic risk assessment induced by heavy metals content of the bottled water in Iran

Recently, the exposure to heavy metals from bottled waters raised huge concerns. In this context, for the first time the risk of non-carcinogenic exposure by the heavy metals in Iranian drinking water was assessed. Therefore, by using the obtained data in our previous published study, the target hazard quotient (THQ) and total target hazard quotient (TTHQ) by considering to the sexuality of consumers were calculated. THQ in females were determined as significantly higher (p??Pb?>?Hg?>?Cd?>?Cu, respectively. The minimum and maximum of THQ for the males were observed in age groups of?+65 and 1–3?years, respectively. The minimum and maximum of THQ for females were noted in age groups of 11–14 and 1–3?years, respectively. Since TTHQ for all ages were less than 1 (p?相似文献   

Prenatal Exposure to Phthalates and Intrauterine Inflammation: A Unifying Hypothesis

We read with great interest the recent paper by Xu et al. (2005),showing that phthalates alter rat placental essential fattyacids (EFA) homeostasis via peroxisome proliferator-activated     

Phthalates rapidly increase production of reactive oxygen species in vivo: role of Kupffer cells

The role of oxidants in the mechanism of tumor promotion by peroxisome proliferators remains controversial. The idea that induction of acyl-coenzyme A oxidase leads to increased production of H(2)O(2), which damages DNA, seems unlikely; still, free radicals might be important in signaling in specialized cell types such as Kupffer cells, which produce mitogens. Because hard evidence for increased oxidant production in vivo after treatment with peroxisome proliferators is lacking, the spin-trapping technique and electron spin resonance spectroscopy were used. Rats were given di(2-ethylhexyl) phthalate (DEHP) acutely. The spin trapping agent alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone was also given and bile samples were collected for 4 h. Under these conditions, the intensity of the six-line radical adduct signal increased to a maximum value of 2.5-fold 2 h after administration of DEHP, before peroxisomal oxidases were induced. Furthermore, DEHP given with [(13)C(2)]dimethyl sulfoxide produced a 12-line electron spin resonance spectrum, providing evidence that DEHP stimulates (*)OH radical formation in vivo. Furthermore, when rats were pretreated with dietary glycine, which inactivates Kupffer cells, DEHP did not increase radical signals. Moreover, similar treatments were performed in knockout mice deficient in NADPH oxidase (p47(phox) subunit). Importantly, DEHP increased oxidant production in wild-type but not in NADPH oxidase-deficient mice. These data provide evidence for the hypothesis that the molecular source of free radicals induced by peroxisome proliferators is NADPH oxidase in Kupffer cells. On the contrary, radical adduct formation was not affected in peroxisome proliferator-activated receptor alpha knockout mice. These observations represent the first direct, in vivo evidence that phthalates increase free radicals in liver before peroxisomal oxidases are induced.