Newcastle Allotments Lead Biomonitoring Study:
Assessing Gardeners’ Lead Exposure in Urban Agriculture Sites to Improve the Derivation of Soil Assessment Criteria
(Lindsay Bramwell, 14/11/24 at 1pm)

In the UK, the current soil screening level for a ‘low level toxicological concern’ for lead in allotments is 80 mg/kg (DEFRA, 2014). This soil screening level is 10 times lower than that observed on many allotments across Newcastle upon Tyne, a city in NE England, with a long industrial heritage. Detailed quantitative risk assessments have been previously carried out on Newcastle’s allotment gardens and Newcastle City Council concluded that, on balance, gardening activities and consumption of vegetables from these sites is a greater benefit than risk to health, however, there is considerable uncertainty in the exposure modelling, with the association between concentrations of lead in soil and blood remaining uncharacterised. The aim of this study was to determine the relationship between concentrations of lead in garden soils and the blood lead concentration of gardeners to give confidence to regulators who must decide the suitability of a site. Participants provided blood and saliva samples and helped the team collect soil, vegetable and fruit samples from their plots. To account for confounders, participants provided tap water samples, home dust samples, atmospheric deposition samples and completed a questionnaire on potential exposure factors.

Registration link: https://attendee.gotowebinar.com/register/2905411539711493726

Part 2A Investigation of Vapour Intrusion from Chlorinated Solvents
(Simon Burr, Campbell Reith, 3/12/24 at 1pm)

Presentation of a case study which covers a Part 2A investigation into contamination of the soils and groundwater at a former dry-cleaners in Ross-on-Wye. The predominant pollutant pathway was associated with vapours from the chlorinated solvent plume which had migrated off site beneath existing residential buildings. The investigation comprised multi-level boreholes, vapour wells, and in-house vapour sampling, both in-house and sub slab. The investigation needed to account for fractured bedrock, potential vapour flow through the unsaturated zone, topographic falls across the wider area, consideration of preferential pathways (sewers) and background solvent concentrations. It also included a detailed communication strategy with emphasis on the off-site residents to enable entry to their properties.

Registration link: https://attendee.gotowebinar.com/register/8842506048864761178