title: Lead in rice: analysis of baseline lead levels in market and field collected rice grains.
abstract: In a large scale survey of rice grains from markets (13 countries) and fields (6 countries), a total of 1578 rice grain samples were analysed for lead. From the market collected samples, only 0.6% of the samples exceeded the Chinese and EU limit of 0.2 μg g(-1) lead in rice (when excluding samples collected from known contaminated/mine impacted regions). When evaluating the rice grain samples against the Food and Drug Administration's (FDA) provisional total tolerable intake (PTTI) values for children and pregnant women, it was found that only people consuming large quantities of rice were at risk of exceeding the PTTI from rice alone. Furthermore, 6 field experiments were conducted to evaluate the proportion of the variation in lead concentration in rice grains due to genetics. A total of 4 of the 6 field experiments had significant differences between genotypes, but when the genotypes common across all six field sites were assessed, only 4% of the variation was explained by genotype, with 9.5% and 11% of the variation explained by the environment and genotype by environment interaction respectively. Further work is needed to identify the sources of lead contamination in rice, with detailed information obtained on the locations and environments where the rice is sampled, so that specific risk assessments can be performed.
authors.affiliation: School of Biological Sciences, University of Aberdeen, Cruickshank Building, St. Machar Drive, Aberdeen AB 24 3UU, Scotland, UK. Electronic address: g.norton@abdn.ac.uk.
authors.forename: Gareth J
authors.initials: GJ
authors.lastname: Norton
authors.affiliation: Institute for Global Food Security, Queen's University Belfast, David Keir Building, Malone Road, Belfast BT9 5BN, Northern Ireland, UK.
authors.forename: Paul N
authors.initials: PN
authors.lastname: Williams
authors.affiliation: Department of Botany, University of Ghana, Legon, Accra, Ghana.
authors.forename: Eureka E
authors.initials: EE
authors.lastname: Adomako
authors.affiliation: School of Biological Sciences, University of Aberdeen, Cruickshank Building, St. Machar Drive, Aberdeen AB 24 3UU, Scotland, UK.
authors.forename: Adam H
authors.initials: AH
authors.lastname: Price
authors.affiliation: Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China.
authors.forename: Yongguan
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China; Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.
authors.forename: Fang-Jie
authors.initials: FJ
authors.lastname: Zhao
authors.affiliation: Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.
authors.forename: Steve
authors.initials: S
authors.lastname: McGrath
authors.affiliation: School of Biological Sciences, University of Aberdeen, Cruickshank Building, St. Machar Drive, Aberdeen AB 24 3UU, Scotland, UK.
authors.forename: Claire M
authors.initials: CM
authors.lastname: Deacon
authors.affiliation: School of Biological Sciences, University of Aberdeen, Cruickshank Building, St. Machar Drive, Aberdeen AB 24 3UU, Scotland, UK.
authors.forename: Antia
authors.initials: A
authors.lastname: Villada
authors.affiliation: School of Biological Sciences, University of Aberdeen, Cruickshank Building, St. Machar Drive, Aberdeen AB 24 3UU, Scotland, UK.
authors.forename: Alessia
authors.initials: A
authors.lastname: Sommella
authors.affiliation: South China Agricultural University, College of Natural Resources and Environment, Guangzhou 510642, Guangdong, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Environmental Science & Engineering, College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Ming
authors.affiliation: Department of Zoology, University of Ruhuna, Matara 81000, Sri Lanka.
authors.forename: P Mangala C S
authors.initials: PMCS
authors.lastname: De Silva
authors.affiliation: 37 Kingsway Court, Hove, East Sussex BN3 2LP, UK.
authors.forename: Hugh
authors.initials: H
authors.lastname: Brammer
authors.affiliation: Calcutta University, 35 B.C. Road, Kolkata 700 019, West Bengal, India.
authors.forename: Tapash
authors.initials: T
authors.lastname: Dasgupta
authors.affiliation: Department of Soil Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh.
authors.forename: M Rafiqul
authors.initials: MR
authors.lastname: Islam
authors.affiliation: Institute for Global Food Security, Queen's University Belfast, David Keir Building, Malone Road, Belfast BT9 5BN, Northern Ireland, UK.
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Meharg
mesh_terms: D003625:Data Collection; D005506:Food Contamination / Q000706:statistics & numerical data; D007854:Lead / Q000032:analysis* / Q000592:standards; D012275:Oryza / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis* / Q000592:standards
chemical_list: D012989:Soil Pollutants; D007854:Lead
keywords: Genetic variation; Lead; Market survey; Rice; Risk assessment