Britain's Health Protection Agency is warning that lead poisoning in children may be a bigger public health issue in the UK than is currently appreciated, and more research needs to be done to establish the exact threat.
The World Health Organisation recommends that attempts are made to ensure that at least 98 per cent of children have blood levels of less than 100µg/l (microgram/litre). There is concern that levels higher than this may lead to neurological and behavioural damage.
However, toxicologists at the Health Protection Agency’s Chemical Hazards and Poisons Division say the level of 100µg/l may not be appropriate for use in the UK and that neurological development may be affected in children with blood lead levels below this concentration.
They say research needs to be done into the effects of lower levels of lead exposure on children in the UK, and the effects of blood lead levels below 100µg/l.
Their call follows US studies which suggest subtle impairment may occur at blood lead levels below 100µg/l. Impairments include a possible decrease in intelligence and subtle neurological changes resulting from children inhaling and ingesting flaking paint containing lead.
Currently no data exists to suggest whether there may be similar effects in the UK and no routine programme exists to monitor any effects. At the moment, the Health Protection Agency is only notified of severe cases of lead exposure (where blood levels exceed 400µg/l or the patient is particularly unwell) when doctors seek advice from the Agency.
Yet many children in the UK are inadvertently exposed to low levels of lead. For example, in buildings where lead-based paint remains, children can inhale or eat lead as the paint peels, chips or is removed. Children are at increased risk from the ingestion of lead-paint chips because of their unique physiology, behavioural patterns and metabolic pathways. Children who exhibit pica behaviour – eat non-food substances – are at even greater risk.
In a presentation at the Agency’s annual Scientific Conference, toxicologist Professor Virginia Murray said, “We are concerned that lead may pose a bigger problem in this country than is realised. Currently we are only alerted of cases by doctors where lead has made children very ill. Yet we fear that lower levels of exposure in this country could also be damaging our children.
“Research is required if we are to establish the effects of low blood lead levels in children and the necessary actions.”
Professor Pat Troop, Chief Executive of the Health Protection Agency, said, “One of the new roles of the Health Protection Agency is to look at some of the effects of long-term chemical exposures as well as the effects from acute incidents. Children are particularly vulnerable and are therefore one of our top priorities. We are working with partners to establish the levels of threat that chemicals such as lead may pose to their health.”