湛江湾陆源入海排污口沉积物中HCHs和DDTs的残留和来源

由于含有DDT的防污漆和林丹曾在我国使用,一些渔港`DDTs和HCHs的残留严重,湛江湾作为我国南方重要的渔港和养殖地区相关研究较少。为评估湛江湾HCHs和DDTs的残留状况和来源,本研究调查分析了湛江湾11个陆源入海排污口沉积物中HCHs和DDTs的含量、空间分布和来源。自1980s以来,研究区域HCHs的残留量明显下降,但DDTs含量变化较小,甚至在一些站位出现较高值。HCHs和DDTs组成和特征比值显示HCHs可能来自湛江湾周围土壤中残留的HCHs和近期少量的输入,DDTs可能来自工业DDTs的历史残留和含有DDTs的防污漆。根据沉积物质量指导,DDTs对海洋环境具有一定生态风险,可能对海洋生物体产生危害。本研究表明林丹和含有DDT的防污漆在湛江可能还有使用,相关部门应该加强控制管理,以及对现有污染区域的治理。     

山东省寿光市土壤中有机氯农药残留分布及来源解析

寿光市土壤中六六六(HCHs)和滴滴涕(DDTs)均有残留。六六六(HCHs)检出率为27.64%,主要残留物为γ-HCH和δ-HCH,平均残留率分别为0.65×10~(-9)和0.50×10~(-9);滴滴涕(DDTs)检出率为59.35%,主要残留物为p,p′-DDE和p,p′-DDT,平均残留率分别为5.21×10~(-9),5.20×10~(-9)。残留量较国内多数其他地区低,仅DDTs稍高于香港土壤和黄淮海地区农田。按土壤环境质量评价标准,HCHs属于一类土壤,DDTs一类土壤占比90.41%,二类土壤占比9.56%。通过对HCHs和DDTs各组分残留量进行比较,寿光市HCHs和DDTs使用时间较久远,多数已降解,但仍有部分地区可能使用过林丹,部分地区有新外源DDTs污染输入。     

重庆老龙洞地下河流域水体有机氯农药污染及来源初步研究

为查明重庆老龙洞地下河流域有机氯农药的污染情况及其特征和来源,通过气相色谱-微池电子捕获检测器(GC-μ ECD)检测水体OCPs含量.结果表明研究区水样中受到了有机氯农药不同程度的污染.α-HCH是研究区水体HCHs主要成分,HCHs的残留主要来自于大气长距离传输.DDTs的主要成分各采样点不尽相同.DDTs的输入为历史上工业DDTs的使用且在水体中其主要以好氧转化为主.与国内外河流相比较,老龙洞地下河流域水体有机氯农药含量处于较高水平.     

天津临港工业区周围海域生物体内滴滴涕(DDTs)和六六六(HCHs)残留

采用气相色谱-质谱联用仪(GC-MS)对2009年4月从天津临港工业区周围海域获得的生物样品进行了测试,研究了该区生物体内DDTs和HCHs含量及分布特征.结果表明,该海域生物体中DDTs的含量相对较高,范围为1.15～25.79 ng.g-1(湿质量),HCHs含量较低,范围为0～7.86 ng.g-1(湿质量).异...     

Organochlorine pesticides characteristics in water column of strategic drinking water sources in the Yangtze estuary

Biandansha, Qingcaosha and Meimaosha sands located respectively in the upper, middle and lower reaches of the Yangtze （Changjiang River） estuary are regarded as strategic drinking water sources of Shanghai City. In the coming decade, the Qingcaosha Reservoir will first be built and gradually take the place of present water sources in the Huangpu River. However, there is little report on the occurrence of persistent organic pollutants （POPs） such as organochlorine pesticides （OCPs） in those strategic water sources. Water samples collected from those strategic water sources were filtered in-situ by Whatman GF/F filters in April 20-23, 2006. Pesticides in the filtrates were enriched on ENVI-18 solid phase extraction （SPE） tubes. OCPs eluted from SPE tubes were determined by GC-μECD method with a mixed standard solution of 20 OCPs compounds. Pentachloronitrobenzene was added as internal standard. Total concentrations of OCPs varied between 15.1 and 83.1 ng/L in water samples from Shanghai strategic water sources. A half of twenty objective OCPs compounds including DDTs were not detected. In Qingcaosha waters, there were six compounds such as a-HCH, dieldrin, endrin, endrin ketone, β-endosulfan and endosulfan sulfate. Total concentrations of these OCPs ranged from 15.1 to 31.6 ng/L and averaged 19.9 ng/L. OCPs had higher concentrations at low water tide than at high water tide, and in bottom water than in surface water. In Biandansha and Meimaosha waters, lindane （T-HCH） of 9.0 ng/L and γ-chlordane of 8.8 ng/L were found, respectively. There was no significant difference between total OCPs concentrations in surface water from Biandansha and Qingcaosha, which are much lower than those in the downstream Meimaosha waters.     

Spatial and vertical distribution of organochlorine pesticides in sediments from Daya Bay, South China

The spatial and vertical distribution of organochlorine pesticides (OCPs) has been investigated in Daya Bay, China. The concentration of total OCPs in surface sediment range from 16.66 to 44.04ng/g dry weight with a mean concentration of 26.60ng/g. DDTs and HCHs were the predominant species. The ratios of (DDD+DDE)/DDT reflected a cocktail input pattern of fresh and weathered DDTs. The predominant alpha-HCH and the alpha/beta-HCH ratios indicated that the technical HCH contamination was mainly due to historical usage, although there was fresh input of lindane. The variation profiles of concentrations showed that OCPs were extensively applied between the late 1950s and early 1980s in China. A recent increasing trend in concentrations of DDTs and HCHs was found in both cores. The increasing ratios of (DDE+DDD)/DDT with corresponding decreases of DDE/DDT ratio implied that most of the DDTs deposited after their production ban were more likely "weathered" DDTs derived from soil residues.     

重庆老龙洞地下河流域水体有机氯农药污染及来源初步研究

为查明重庆老龙洞地下河流域有机氯农药的污染情况及其特征和来源,通过气相色谱-微池电子捕获检测器(GC-μECD)检测水体OCPs含量。结果表明研究区水样中受到了有机氯农药不同程度的污染。α-HCH是研究区水体HCHs主要成分,HCHs的残留主要来自于大气长距离传输。DDTs的主要成分各采样点不尽相同。DDTs的输入为历史上工业DDTs的使用且在水体中其主要以好氧转化为主。与国内外河流相比较,老龙洞地下河流域水体有机氯农药含量处于较高水平。     

湖泊水体中HCHs沉降通量及其与浮游植物间响应关系

于2006年跨春夏秋三季对一封闭的小型湖泊水体中颗粒物的沉降通量和浮游植物生物量进行了采样调查,测定了沉降颗粒物中的TOC含量和六六六（HcHs）含量。结果表明,湖水中浮游植物在春末以及秋季密度较大,浮游植物密度、叶绿素含量和总悬浮颗粒物浓度总体变化趋势基本一致,说明水体总悬浮颗粒物浓度与浮游植物生物量密切相关;春季颗粒物沉降通量较大,且与总悬浮颗粒物浓度和叶绿素含量之间存在一定的滞后性,夏季和秋季颗粒物沉降通量保持在一个较低水平;HCHs的沉降通量呈现春季较大的现象,与颗粒TOC沉降通量变化趋势相一致,表明HCHs的沉降主要受颗粒TOC沉降通量的控制。     

加速溶剂萃取-气相色谱/质谱法同时测定土壤中拟除虫菊酯类等18种农药残留

采用正己烷-丙酮-磷酸混合溶剂为提取剂,在萃取温度100℃、压力10.3 MPa条件下,用快速溶剂萃取仪提取土壤样品,石墨碳黑氨基固相萃取柱净化,PTV大体积进样,气相色谱-质谱联法同时检测六六六(HCHs)、滴滴涕(DDTs)和10种拟除虫菊酯类农药(联苯菊酯、甲氰菊酯、氯氟氰菊酯、氯菊酯、氯氰菊酯、氟氯氰菊酯、氟氨氰菊酯、氰戊菊酯、氟氰戊菊酯、溴氰菊酯)共18种农药残留。在10～20μg/kg的添加浓度下,目标化合物平均回收率为82.84%～96.33%,相对标准偏差(RSD,n=6)为3.21%～7.34%;在20～40μg/kg的添加浓度下,目标化合物平均回收率为80.55%～103.76%,RSD(n=6)为2.56%～5.78%;在40～80μg/kg的添加浓度下,目标化合物平均回收率81.56%～95.38%,RSD(n=6)为2.19%～5.88%。方法检出限为0.11～3.40μg/kg,实际样品检测的RSD(n=3)为4.94%～8.74%。方法简单快速、灵敏度高、准确度好,可以满足土壤中HCHs、DDTs和拟除虫菊酯类农药残留的实际检测需要。     

Persistent organochlorine residues in sediments from the Black Sea

The extent of contamination of the Black Sea by selected organochlorine compounds has been assessed through the analysis of surficial sediments taken from throughout the region. Concentrations of HCHs at sites influenced by the Danube delta are among the highest recorded on a global basis (up to 40 ng g(-1) dry wt). The ratio between the alpha- and gamma-isomers was relatively low indicating contamination through the use of lindane. Concentrations of DDTs (0.06-72 ng g(-1) dry wt) and PCBs (0.06-72 ng g(-1) dry wt) were not especially high in comparison to levels reported from throughout the world. The DDE/DDT ratio was, however, low indicating fresh inputs and hence current usage of DDT within the Black Sea region.