Commentary: flawed science delays smelter cleanup and worsens health

Chemicals Denial—A Challenge to Science and Policy

Much research shows that science denial regarding climate change is widespread and problematic for science and scientists, as well as for policy-makers. Climate denial delays goal achievement. As shown in this article, science denial commonly occurs also in the field of chemicals assessment and policy, but the research on the topic is scarce. The peer-reviewed studies that exist mostly concern a limited number of specific cases, such as DDT, CFCs and endocrine disrupting chemicals. The characteristics of ‘chemicals denial’ show similarity with those of climate denial, including reliance on fake experts, cherry-picked facts and attacks on scientists, with a key aspect being the questioning of causal relationships. Considering the gaps between chemicals policy goals and the state of the environment, further scientific exploration in the field is needed. Developing a better coordinated research agenda and a common terminology are therefore warranted strategies. A key concept in such endeavors could be ‘chemicals denial’.

The effect of contemporary mine emissions on children's blood lead levels

BACKGROUND

Broken Hill is home to Australia's oldest silver-zinc-lead mine. However, the precise source of childhood blood lead (PbB) exposures has been subject to considerable debate. Lead sources include natural soil Pb enrichment, legacy deposition, contemporary mining emissions, and Pb-based paint.

OBJECTIVE

To test whether contemporary mining emissions independently affect childhood PbB in Broken Hill.

METHODS

Children's (<5 years old) PbB measures from 2011 to 2015 (n = 4852), obtained from Broken Hill Child & Family Health Centre, were analyzed using generalised linear regression models, including covariates of household soil Pb, city dust Pb concentrations (PbD), demographic factors and Pb ore production. Two natural experiments involving wind direction and the 2009 dust storm were examined to test whether the PbB-distance gradient from the mining operations was influenced by contemporary emissions. The influence of contemporary emissions was further interrogated by examining the effect of ore production on PbB and PbD.

RESULTS

Children living downwind and proximate to the mine had substantially higher PbB outcomes than children similarly distant but upwind. Dust Pb deposition increased significantly with proximity to mining operations as well to Pb production (1991-2013). Average annual PbB correlated with Pb ore production (p < 0.01) with all subsets of children PbB levels responding with near unit elasticity to Pb ore production (p < 0.01). Pre- and post-analysis of the dust storm showed the PbB-distance gradient remained statistically unaltered further confirming contemporary emissions as a source of exposure.

CONCLUSIONS

Contemporary mining emissions influence children's PbB measures independent of other sources and need to be remediated to facilitate reductions in harmful exposure.