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261.
We quantified the contents of four toxic metals in cosmetic products that are commercially available in Jordan; 112 cosmetics, representing 10 product types, were tested in triplicate after acid digestion using inductively coupled plasma optical emission spectrometry and a mercury analyzer. Ni was most abundant, detected in 104/112 (92.8%) products (average, 2.32 ppm; and median, 1.47 ppm); 66/112 (59%) contained >1 ppm and 13/112 (11.6%), >5 ppm Ni. Cd was second-most abundant, detected in 86/112 (76.7%) products (mean, 1.71 ppm; range from< detection limit [DL] to 18.07 ppm); 16 products (14.3%) exceeded the 3 ppm suggested limit. Pb was detected in 82/112 (73.2%) products (mean, 7.8 ppm; range, < detection limit to 190.43 ppm); 20/112 (17.8%) contained more than the suggested 10 ppm limit. Hg was least-frequently detected, present in 29/112 (25.9%) and at >3 ppm in 15/112 (13.4%) products. The highest content of Hg was observed in skin lightening creams (mean concentration, 1,008 ppm). Hg was detected in 20 (62.5%) of the 32 skin lightening creams tested, of which 11/32 (34.4%) contained > 3 ppm Hg. Of the 112 cosmetics tested, 17 (15.1%) products contained Ni, Pb, Cd, and Hg; 19/112 (16.9%) contained Cd, Pb, and Hg –no product exceeded the maximum acceptable limits for all three elements, and 9/112 (8%) products exceed the maximum recommended levels for at least two elements (Hg, Cd, and Pb). 相似文献
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电解法处理废料贵铅的电极极化研究 总被引:1,自引:1,他引:0
以含金银铅废料制成贵铅为原料,利用电化学热力学和动力学理论,对贵铅电解法实现金银与铅的分离和得到纯铅的电极过程极化行为与工艺条件的关系进行了研究。从而确定了贵铅电解时的电解液组成为[pb2+]70g/L,温度为40℃,β-萘酚/胶联合添加剂等工艺条件.同时根据动力学的研究证明了贵铅电解的电极反应速度受扩散控制,其扩散速度常数K扩=1.917×10-3cm/s。扩散层厚度为0.0051cm,在ηk=75mV时的阴极过程活化能为16.10kJ/mol,为贵铅电解工业分离回收金银铅提供了可靠的理论依据和设计参数。 相似文献
266.
溶解有机物(DOM)是决定水环境中铅(Pb)的形态、环境行为和生态风险的重要因子.然而,落叶DOM与Pb(II)络合作用的调控机制尚不清楚.光和微生物降解是调控DOM含量、组成与活性的两个关键过程.本研究运用降解培养实验、光谱学表征和荧光猝灭滴定,考察光和微生物降解单独作用和共同作用对芦苇落叶DOM的改造及其对DOM与Pb(II)相互作用的影响.激发-发射三维荧光光谱-平行因子分析共识别出4个类腐殖质组分(C1~C4)和1个类蛋白质组分(C5).类腐殖质组分更容易被光降解,类蛋白质组分则被微生物优先利用,光降解在短期的光-微生物降解过程中起主导作用.对于原始落叶DOM,Pb(II)主要与类腐殖质组分C1、C2和C4络合,C3组分只在光-微生物降解后的样品呈现显著荧光猝灭,类蛋白质组分C5在光和光-微生物降解后开始参与络合.类腐殖质C1与Pb(II)络合的条件稳定常数logKM在光降解后升高而在光-微生物降解后下降,C2和C4的logKM值经过各降解过程后均升高.降解后这3个组分参与络合的比例f和络合容量Fmax·f均显著降低,且光降解的影响显著高于微生物降解.这些结果表明,光降解和微生物降解对DOM丰度、组成和结构的改造将显著影响其与金属离子的络合稳定性和络合容量. 相似文献
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Massadeh A Al-Sharif L Dalale'h R Hassan M 《Environmental monitoring and assessment》2006,115(1-3):87-93
A total of two hundred and forty random samples were collected equally from mutton, liver and kidney of 40 local (Jordanian) and 40 imported Australian sheep (40 each sub sample). Fresh samples were collected from 12–18 m old sheep slaughtered in abattoirs in Jordan in 2002. Besides, 40 fresh mutton samples of imported Chinese sheep were collected from different markets. Atomic absorption spectrometry (AAS) was used to estimate the lead (Pb) content of the samples. Results indicated that Australian mutton had significantly higher (p < 0.05) mean of lead pollution than that of the local and Chinese muttons. The mean concentration of lead (mg/kg) in Australian, local and Chinese muttons was 4.30, 3.15 and 2.17, respectively. The mean concentration of lead in Australian sheep liver was significantly higher (p < 0.05) than that recorded in the local sheep liver. The mean concentration of Pb in Australian and local sheep liver was 5.69 and 4.52 mg/kg, respectively. The mean concentrations of Pb in the kidney of the Australian and local sheep were not significantly different (p > 0.05). They were 4.59 and 3.87 mg/kg, respectively.On the basis of the samples lead level, 85, 92 and 87.5% of local, Australian and Chinese mutton respectively, exceeded the international safe permissible limit of 1.0 mg/kg. Furthermore, the effect of Pb on animal and human health was discussed. 相似文献
269.
Coşkun M 《Environmental monitoring and assessment》2006,121(1-3):173-178
Austrian pine (Pinus nigra) bark was collected in thirty-seven localities in the Thrace region, Turkey, for the determination of airborne toxic metal distribution. Five toxic metals, As, Cd, Cu, Pb, and Zn, were monitored using atomic absorption spectrometry. Distribution maps of toxic elements in the region were plotted according to Geographic Information System technology. In general, the concentrations of all investigated elements were not high in the region apart from the vicinity of big cities, Tekirdag, Istanbul and, close to Bulgarian border. However, the highest concentrations were not at pollution level. They have a similar distribution pattern throughout the region. 相似文献
270.
上海市黄浦江水源地重金属铅、镉多介质富集特征分析 总被引:5,自引:0,他引:5
上海市黄浦江饮用水源地的水质直接影响到上海市近1 700万居民的日常生活和健康安全,因此通过现场采集及室内分析对上海市主要饮用水源地黄浦江上游干流河段表层水体,表层沉积物及支流表层水体及其周边表层土壤中重金属铅、镉类污染物的含量进行了检验。结果表明:黄浦江干流表层水体铅平均含量为3234 μg/L,镉平均含量为022 μg/L;支流水体中铅平均含量为086 μg/L,镉平均含量为013 μg/L;支流表层沉积物中铅平均含量为327 μg/g,干流平均含量为218 μg/g,周边土壤中铅含量除个别点外稳定在2022~3903 μg/g;沉积物中镉的平均含量为03 μg/g,土壤中镉含量基本在015 μg/g左右。通过分析该区域多介质中重金属铅、镉的富集特征,判断表层沉积物是该区域重金属铅、镉的主要富集介质;该区域铅污染的主要受周边土壤的淋溶冲刷作用影响;2号(斜塘与圆泄泾交汇处),4号(竖潦泾与横潦泾交汇处)采样点区域相对于其他各采样点区域有短期、低浓度的重金属镉输入. 相似文献