The Institute for Health Metrics and Evaluation (IHME) estimated that in 2017, lead exposure accounted for 1.06 million deaths and 24.4 million years of healthy life lost (disability-adjusted life years (DALYs)) worldwide due to long-term effects on health.
The Institute for Health Metrics and Evaluation (IHME) estimated that in 2017, lead exposure accounted for 1.06 million deaths and 24.4 million years of healthy life lost (disability-adjusted life years (DALYs)) worldwide due to long-term effects on health.
WHO has identified lead as 1 of 10 chemicals of major public health concern, needing action by Member States to protect the health of workers, children and women of reproductive age.
Centers for Diesease Control and Prevention regarding Lead (Pb) states “No safe blood lead level in children has been identified”
Public Health for England (formerly the Health Protection Agency) in their Lead Toxological Overview say
“Studies in children have reported neurobehavioral effects in children at a blood lead (PbB) level of <10 μg dL-1. There appears to be no clear threshold for the neurodevelopmental effects in children.”
The Agency for Toxic Substances & Disease Registry (ATSDR, 2015) lists Pb as second on their hazardous substances priority listing which is based on frequency of occurrence, toxicity, and potential for human exposure to the substance.
Similarly in the UK a review of sites determined under Part2A contained in a report on the state of contaminated land indicated that Lead was second most common contaminant on which sites had been determined.
Distribution of lead in near surface arises both from diffuse anthropogenic pollution sources and from soils derived from rocks affected by mineralisation. For Natural Background Concentrations (NBC) of lead for England and Wales in areas of mineralisation and for urban environments see http://randd.defra.gov.uk/Document.aspx?Document=10333_TGS_Pb_FINAL.PDF
It is noted that the oral bioaccessibility may vary between different lead sources. Based on the paper produce by Palmer, S. et al, (2015). ‘The Effects of Lead Sources on Oral Bioaccessibility In Soil And Implications for Contaminated Land Risk Management‘ this fact may have a bearing on health risks in areas with high NBC where such forms of contamination would not be considered statutory Contaminated Land unless according to the guidance there was a good reason to deem otherwise.
Interestingly, whilst concerns over the use of bioaccessibility criteria in deriving generic screening values was set out in the Development of Category 4 Screening level Main Report it was taken account in the derivation of the lead C4SL (see Appendix H to the main report)
Lead emissions in the UK have dropped considerably since the phasing out of leaded petrol with emissions according to a 2006 DEFRA report dropping from 7465.9 tonnes per annum in 1970 to 162 tonnes per annum in 2002.
Lead was used in water supply pipework prior to 1970 and properties older than 1970 may still contain lead for more advice go to http://dwi.defra.gov.uk/consumers/advice-leaflets/lead.pdf.
Lead in drinking water remains a concern as the current Drinking Water Standard (DWS)of 10ug/l is considered high with a proposed reduction in the European drinking water standards to 5ug/l. Furthermore, the DWI has found that where meters are fitted to supplies with lead plumbing there is an increase in lead concentration significantly higher than the current DWS, although this may be mitigated by flushing.. ( see Assessing the effect of water meter installation on exposure to lead in water – Drinking Water Inspectorate (dwi.gov.uk) ) from recent research by the DWI it would appear that those at greatest risk of from lead DWS exceedances on public supplies are those with lead pipework where there is no phosphate dosing. Consequently, removal of lead pipework up to the compliance point (normally the consumer’s kitchen tap) would need to be a key part of any strategy to achieve the talked about 5ug/l reduction being considered, something which the most recent research suggest may not be a cost benefit if unilaterally applied across England and Wales (see Long-term Strategies to Reduce Lead Exposure from Drinking Water – Drinking Water Inspectorate (dwi.gov.uk))
