Volume 199 - Issue 5
Eliminating childhood lead toxicity in Australia: a call to lower the intervention level
Authors: Mark P Taylor, Bruce P Lanphear and Chris Winder
Med J Aust 2013; 199 (5): 323-324. || doi: 10.5694/mja13.10261
Published online: 2 September 2013
Published online: 2 September 2013
In reply: In epidemiology, the weight-of-evidence approach is useful for reaching general conclusions, whereas details from selected studies are useful for understanding nuances. This is particularly important when evidence from human and experimental research is consistent across multiple studies and in populations with different characteristics, including Australia.1-3 There will always be limitations and unmeasured confounders, but, ultimately, we can rely on controlled laboratory studies which ...
In reply: In epidemiology, the weight-of-evidence approach is useful for reaching general conclusions, whereas details from selected studies are useful for understanding nuances. This is particularly important when evidence from human and experimental research is consistent across multiple studies and in populations with different characteristics, including Australia.1-3 There will always be limitations and unmeasured confounders, but, ultimately, we can rely on controlled laboratory studies which show that lead is toxic, even at picomolar concentrations.1,4
Recent independent and expert scientific reviews — including reviews from the World Health Organization, Germany’s Human Biomonitoring Commission and US national agencies such as the Agency for Toxic Substances and Disease Registry, Centers for Disease Control and Prevention, National Toxicology Program and Environmental Protection Agency — have issued recommendations to reduce the public health risks of lead exposure. A February 2013 report by Health Canada confirms that effects have been associated with blood lead levels as low as 1–2 μg/dL.5 These reviews indicate that the current National Health and Medical Research Council guideline for lead (10 μg/dL) is too high and should be revised downwards.
Competing interests
No relevant disclosures.
References
- Lanphear BP, Hornung R, Khoury J, et al. Low-level environmental lead exposure and children’s intellectual function: an international pooled analysis. Environ Health Perspect 2005; 113: 894-899.<eMJA full text>
- Lanphear BP, Hornung RW, Khoury J, et al. The conundrum of unmeasured confounding: Comment on “Can some of the detrimental neurodevelopmental effects attributed to lead be due to pesticides? by Brian Gulson.” Sci Total Environ 2008; 396: 196-200. 0_pgfId-2857191
- Earl R. An investigation of the effects of lead on children’s cognitive abilities [PhD thesis]. Adelaide: University of Adelaide, 2011. http://digital.library.adelaide.edu.au/dspace/handle/2440/71322 (accessed Jul 2013).
- Scheider JS, Huang FN, Vemuri MC. Effects of low-level lead exposure on cell survival and neurite length in primary mesancephalic cultures. Neurotoxicol Teratol 2003; 25: 555-559. 0_i1142865
- Health Canada. Final human health state of the science report on lead. Ottawa: Health Canada, 2013. http://hc-sc.gc.ca/ewh-semt/pubs/contaminants/dhhssrl-rpecscepsh/index-eng.php (accessed Jul 2013).