Survey Data on Lead in Women's and Children's Vitamins

In early 2007, FDA became aware of reports of elevated lead levels in certain vitamins, which became an issue of concern to FDA, Congress, and the public. This survey was conducted to determine the content of lead (Pb) in vitamins labeled for women and children. The Pb content of 324 multivitamin-mineral products purchased over the Internet was determined using microwave assisted nitric acid digestion and inductively coupled plasma mass spectrometry.¹ Cryogenic grinding was used to composite soft samples such as oil filled capsules and candy-like products such as gummies and jelly beans. The median and maximum mass fractions were 0.160 and 2.40 mg/kg, respectively. Only four samples exceeded 1 mg/kg.

Estimates of Pb exposures from consumption of products were derived by multiplying the maximum recommended daily serving provided by the label instructions by the Pb mass fractions (i.e., concentrations) determined in this study. The overall median value for Pb exposure was 0.576 µg/day. Five samples would have provided exposures that exceeded 4 µg/day, the highest being 8.97 µg/day. The highest exposure estimate for children's vitamins was 2.88 µg/day. Estimates of exposures were assessed with respect to safe/tolerable exposure levels that have been developed for particular age and sex groups. These safe/tolerable exposure levels are referred to as the provisional total tolerable intake levels (PTTI)².

Estimates of Pb exposures for all products were below the PTTI levels for the at-risk population groups of children, pregnant and lactating women and adult women. Table 1 lists the PTTI levels and summarizes results for mass fraction and estimated exposure by population group. Median and maximum values were used instead of mean and standard deviation due to the skewed distribution of results toward lower mass fraction and exposure as seen in Figures 1 and 2. Table 2 provides a complete listing of Pb mass fractions and estimated Pb exposure values for the samples.

Figure 1. Frequency Distribution of Pb Mass Fractions

Figure 2. Frequency Distribution of Estimated Pb Exposures

References:

1. ¹Mindak, W. R., Cheng, J., Canas, B. J., Bolger, P. M. Lead in women's and children's vitamins. J. Agric. Food Chem. 2008, 56, 6892-6896.
2. ²Carrington, C. D., Bolger, P. M. An assessment of the hazards of lead in food. Regul Toxicol Pharmacol 1992, 16, 265-272.