Further investigations are being undertaken as a precautionary measure following a finding of lead in one sample in each of five primary schools in Dunedin.
Lead is commonly found in New Zealand soil with sources of lead in urban soil including natural background levels, lead based paints, lead from petrol and certain industrial workplaces.
Although the levels of lead in all five schools are above the Ministry for the Environment standard for residential land where there is some consumption of home-grown fruit and vegetables, they are lower than the standard for recreational areas. The standards are triggers for follow up and do not indicate the presence of a definite health risk.
Generally lead in soil poses little harm so long as there is good ground cover, usually grass to prevent dust, and simple preventative actions are taken - like washing hands before eating.
Although the health risk from lead in soil at the level found in these five Dunedin schools is very low, a very conservative approach is being taken and further investigations are being undertaken.
The levels were found as a result of a broader geoscience survey undertaken last year by GNS Science. The levels found are part of wider preliminary findings, which will be incorporated into a geoscience report currently being worked on.
Advice about avoiding harm from lead in soil has been provided to the schools and families of children attending the schools. This is also available on the Ministry of Health website, from Healthline 0800 611 116, from Public Health South 03 476 9800, and by clicking here.
Further advice to the school will depend on the results of the site assessments and, if needed, additional testing will be carried out.
Further assessments are underway relating to seven other non-school sites across the city, and one recreational site.
· Lead is often present in soil and at high concentration can cause health problems, particularly in children under 5 years of age. The most likely way for a child to be exposed to lead is by eating large amounts of lead-containing soil
· A site specific approach is taken for determining appropriate levels of lead in each of the five primary schools
· The standard for homes where home produce is grown and eaten is 210 milligrams of lead per kilogram of soil; for high density housing it is 500 milligrams of lead per kg of soil and for recreational areas the standard is 880
· The higher level of 880 may be appropriate for some primary schools, and the lower limit for others depending on the factors such as whether there are any children with a condition that makes them more likely to eat soil and where the elevated levels are found
· Additional investigations of all five primary schools are underway and public health advice has been provided to the school. Once further results are available these will be shared with the school community and public health staff will be available to answer questions from staff or families
· Where higher levels are found, the advice is to maintain good ground cover – such as grass – and to wash hands before eating food
· Higher levels found in particular spots can also be fenced off to keep people out, or they can have a more permanent cover and the site put to an alternative use.
· The five primary schools are Bathgate Park School, George St Normal School, Mornington School, North East Valley Normal School and Opoho School.