陶瓷食具容器卫生标准中重金属分析方法的改进研究

Improving Analytical Methods for Ceramic Food Containers in National Hygienic Standard

目的对GB/T5009.62—2003《陶瓷食具容器卫生标准的分析方法》进行修订和补充,并为修订GB13121—1991《陶瓷食具容器卫生标准》提供技术支持。方法建议在新修订的GB/T5009.62中保留火焰原子吸收光谱法(FAAS);删除双硫腙比色法(DSMP);增加电感耦合等离子体质谱法(ICP-MS)和石墨炉原子吸收光谱法(GFAAS)。通过开展方法学研究和实验室间比对实验,优化了ICP-MS和GFAAS的检测条件和技术参数。结果采用ICP-MS和GFAAS测定陶瓷食具容器中铅溶出量的定量限(LOQ)分别为1.0和2.5μg/L;测定镉溶出量的定量限(LOQ)均为0.1μg/L;测定铅的实验室间加标回收率为89.0%～114%(ICP-MS)和88.2%～110%(GFAAS);测定镉的实验室间加标回收率为86.2%～94.0%(ICP-MS)和90.0%～108%(GFAAS)。应用ICP-MS和GFAAS对60份产地不同的陶瓷食具容器样品进行铅、镉溶出量检测,经配对样品t检验计算表明结果差异无统计学意义。结论采用ICP-MS和GFAAS测定痕量铅、镉是目前最先进的分析技术,具有很高的灵敏度和准确度。ICP-MS可同时检测陶瓷食具容器中各种金属离子的溶出迁移情况。鉴于新修订的GB/T13121会对不同生产工艺和类型的产品分别制定更严格的铅、镉溶出限量指标,故将以上两种分析技术引入GB/T5009.62十分必要。

Objective To revise GB/T 5009.62—2003 and provide technical support for the revision of GB13121— 1991 Hygienic standard for ceramic food containers.Method It is suggested to keep flame atomic absorption spectrometry（FAAS） in,remove dithizone colorimetry（DSMP） from,add inductively coupled plasma mass spectrometry（ICP-MS） and graphite furnace atomic absorption spectrometry（GFAAS） to the latest edition of GB /T 5009.62.The detecting conditions and technical parameters for ICP-MS and GFAAS were optimized through researches on methodology and interlaboratory comparison.Results The migration of lead and cadmium from ceramic food containers were detected by ICP-MS and GFAAS.The limit of quantitation（LOQ） of lead was 1.0 μg /L（as ICP-MS） and 2.5 μg /L（as GFAAS）,and the LOQ of cadmium was 0.1 μg /L（both ICP-MS and GFAAS）.The recovery rate of adding standards of lead rates were 89.0%-114%（as ICP-MS） and 88.2%-110%（as GFAAS）,and the recovery rates of adding standards of cadmium were 86.2%-94.0%（as ICP-MS） and 90.0%-108%（as GFAAS） in the inter-laboratory.The migration of lead and cadmium from 60 ceramic food container samples produced from different origins were tested by ICP-MS and GFAAS,no statistically significant differences between these two methods were observed by paired t-test.Conclusion ICP-MS and GFAAS are the most advanced analytical technology with high sensitivity and accuracy in detecting trace amount of lead and cadmium.The migration of many trace metals released from ceramic surface could be detected at the same time by ICP-MS.As the GB /T 13121 is going to be revised,more stringent limits for the migration of lead and cadmium from products made by different technologies might be stipulated.Introducing ICP-MS and GFAAS to GB /T 5009.62 is necessary.