排序方式: 共有19条查询结果,搜索用时 15 毫秒
11.
Mei-Hui Li 《毒物与环境化学》2013,95(3):566-573
Fourteen benzophenone-type UV filters and four paraben preservatives were selected to examine their acute toxicities on Dugesia japonica. The 48-h LC50 values for planarians exposed to benzophenone-type UV filters can be ranked as oxybenzone?>?mexenone?>?5-chloro-2-hydroxybenzophenone?> 2,4-dihydroxybenzophenone?>?2-hydroxybenzophenone?>?dioxybenzone?>?benzophenone?>?2,2′,4,4′-tetrahydroxybenzophenone?>?4-hydroxybenzophenone?> 3-hydroxybenzophenone?>?4,4′-dihydroxybenzophenone?>?2,2′-dihydroxy-4,4′-dimethoxybenzophenone?>?2,3,4-trihydroxybenzophenone?>?sulisobenzone with a range from 0.9 to 145?mg?L?1 with a similar sequence for the 96?h LC50 values, ranging from 0.5 to 77?mg?L?1. The 48 and 96?LC50 values for planarians exposed to paraben preservatives can be ranked as butylparaben?>?propylparaben?>?ethylparaben?>?methylparaben. Among all the tested chemicals, oxybenzone was the most toxic and sulisobenzone the least toxic chemical to planarian at each exposure period. Most benzophenone-type UV filters are toxic to aquatic animals with 48?h LC50 values less than 10 mg?L?1, except for 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2,3,4-trihydroxybenzophenone, and sulisobenzone. Because of their common occurrence in aquatic environment, more studies on aquatic toxicities of benzophenone-type UV filters and paraben preservativs are needed to provide important information to adequately assess their ecological risk. 相似文献
12.
Mei-Hui Li 《毒物与环境化学》2013,95(7):1157-1170
Pharmaceutically active compounds are produced worldwide and consumed in large quantities, so these chemicals are frequently detected in limnic environments posing potential ecological risks. Thirty pharmaceutically active compounds were selected for examination of their acute toxicity for freshwater planarians (Dugesia japonica). Among the 30 compounds tested, diclofenac, mefenamic acid, naproxen, propranolol HCl, and diphenhydramine HCl had a 48-h nominal LC50 below10 mg L?1, and for 18 chemicals, it exceeded 100 mg L?1. The 96-h nominal LC50 was below 10 mg L?1 for diclofenac, mefenamic acid, naproxen, propranolol HCl, diltiazem HCl, diphenhydramine HCl, hydroxyzine HCl, and triprolidine HCl, and for 15 chemicals, it exceeded 100 mg L?1. Among different therapeutic groups, analgesics were most toxic to planarians, and antibiotics were least toxic. Antihistamines and beta blockers varied in their acute toxicity to planarians. At the current environmental levels, none of the tested pharmaceutically active compounds may have acutely harmful impacts on aquatic invertebrates. To answer the question whether chronic, long-term exposure to pharmaceutically active compounds may entail ecological risks for aquatic ecosystems, further investigations with different end points in multiple species tests are needed. 相似文献
13.
目的是研究金银花黄色素的最佳提取工艺条件。采用正交试验法,以提取剂与原料用量比(A)、提取时间(B)、微波功率(C)和提取次数(D)4个因素,每个因素选取3个水平进行实验,提取次数与微波功率对提取有极显著影响。其最佳工艺条件为:提取剂为无水乙醇,提取剂与原料用量比为1:50(g/ml),提取时间为50s,微波功率为700W,提取次数为3次。 相似文献
14.
Perfluorooctanoic acid (PFOA) is an emerging persistent organic pollutant that is considered as a neurotoxicant in animal studies. However, these neurotoxicological studies did not evaluate potential neural deficits in aquatic animals associated from PFOA exposure. In this study, the effects of PFOA on neural genes expression and neuronal morphology in the planarian Dugesia japonica have been investigated. The results show that PFOA exposure results in neural-related genes expression alteration and neuronal morphology defects in planarians. These results suggest that the planarian D. japonica is a good bioindicator for the detection and evaluation of PFOA effects on freshwater invertebrates. The basal phylogenetic position of planarians makes them a good indicator species that can predict toxicity for higher taxa, providing information for the overall ecological toxicity of PFOA in aquatic environment. 相似文献
15.
Mei-Hui Li 《毒物与环境化学》2013,95(6):984-991
Many chemicals commonly occurring in surface water are found to be hormonally active. Fourteen compounds including four sex hormones, three synthetic hormones, one non-steroidal anti-androgen, and six industrial endocrine-disrupting chemicals were selected to examine their acute toxicities on the freshwater planarian, Dugesia japonica. Among all test chemicals, diethylstilbestrol had the highest toxicity. Relatively, the toxicities of the synthetic hormones were higher than the natural ones. Among the six industrial endocrine-disrupting chemicals tested, bisphenol A was the most toxic, with a 48-h LC50 of 8.3 mg L?1. Overall, the natural or synthetic hormones, other than estrone and estriol, were more acutely toxic to planarians than the industrial endocrine disruptors tested. The acute toxicities of the test chemicals to Dugesia japonica were in the same order of magnitude as those to Daphnia magna based on available published data. Despite this study used non-environmentally relevant levels, such kinds of chemicals do not exist singly in the aquatic environment, but typically act in synergistic and/or additive ways in the complex environmental mixtures, and the total estrogen equivalents are much higher than a single chemical. This study stands as a starting point for other acute and chronic assays, namely using mixtures. 相似文献
16.
17.
洗涤剂磷对日本三角涡虫生长的影响 总被引:2,自引:0,他引:2
观察了含磷量不同的洗衣粉溶液对日本三角涡虫生长的影响。结果表明:无论洗衣粉含磷量高低对日本三角涡虫生长均有毒害影响,且高磷洗衣粉对涡虫的毒害远大于低磷洗衣粉,磷量的增加与涡虫死亡率呈正相关。实验中,自来水对照组对涡虫生长无影响。 相似文献
18.
铜、汞、铅对涡虫的急性毒性作用 总被引:12,自引:0,他引:12
在恒温 (2 0± 1)℃条件下研究了铜、汞、铅离子对东亚三角头涡虫 (Dugesiajaponica)的急性毒性作用 .结果为Cu2 、Hg2 和Pb2 对涡虫 2 4h半致死浓度 (LC50 )分别是 :1.5 6 3mgL-1、0 .70 4mgL-1和 188.16mgL-1;4 8h的LC50 分别是 :0 .888mgL-1、0 .6 6 6mgL-1和 171.5 7mgL-1;72h的LC50 分别是 :0 .786mgL-1、0 .6 6 2mgL-1和 14 0 .94mgL-1;96h的LC50 分别是 :0 .779mgL-1、0 .6 4 7mgL-1(Pb2 无此值 ) .试验结果表明 :这些重金属的作用应属于3种类型 ,涡虫作为重金属污染的指示生物基本可行 .图 2表 1参 18 相似文献
19.
Mei-Hui Li 《毒物与环境化学》2013,95(8):1174-1184
Regeneration is a vital physiological process for survival of adult organisms. Bisphenol A (BPA), diethystilbestrol (DES), 17α-ethinylestradiol (EE2), and 17β-estradiol (E2) were examined for their effects on head formation in decapitated freshwater planarians (Dugesia japonica). The median lethal concentration of the test chemicals and the median inhibitory concentration for decapitated planarians and different regenerative endpoints, were determined for 3–7 d of exposure. For planarian head regeneration, the no-observed-effect level of BPA and DES was 0.05 mg L?1 and 1 mg L?1 for EE2 and E2. The effects of BPA, DES, and EE2 on asexual planarian regeneration did not correspond with the order of their estrogenic potencies, suggesting that the effects, at least partially, were due to general toxicity rather than their estrogenicity. In view of the published data on concentrations of xenoestrogens in water bodies versus the nominal levels tested here, this study suggests that the current environmental levels of BPA, DES, EE2, and E2 have no immediate adverse effects on freshwater planarian regeneration. 相似文献