Nickel and associated metals in New Caledonia: Exposure levels and their determinants

Abstract

The ultramafic massifs of the New Caledonian archipelago contain about 10% of the world's nickel reserves, which also contain significant but lower amounts of cobalt, chromium, and manganese. Natural erosion of these massifs and mining activities may contribute to the exposure of local populations to these metals through contamination of air, food, and water resources. We conducted a biomonitoring survey to evaluate exposure to these four metals and its main determinants by constructing a stratified sample of 732 adults and children (>3 years old) from visitors to 22 health centers across the archipelago. Urine was collected and analyzed by inductively-coupled plasma mass spectrometry to determine metal concentrations. A face-to-face interview was conducted to document sociodemographic characteristics, lifestyle and dietary habits, and residence-mine distance. Environmental samples (soil, house dust, water, and foodstuffs) were collected from two areas (one with and one without mining activity) to delineate determinants of exposure in more detail. Nickel and chromium were metals with the highest concentrations found in urine, especially in children, at levels exceeding reference values derived from representative national surveys elsewhere throughout the world (for children: 4.7 μg/g creatinine for nickel and 0.50 μg/g creatinine for chromium): 13% of children exceeded the reference value for nickel and 90% for chromium. Large variations were observed by region, age, and sex. In this geological setting, urinary and environmental nickel concentrations appear to be driven mainly by soil content. This is the first archipelago-wide survey of metal exposure in New Caledonia. The potential health consequences of this chronic high exposure need to be assessed.

International Analysis of Sources and Human Health Risk Associated with Trace Metal Contaminants in Residential Indoor Dust

“…These unique differences reflect local anthropogenic activities adjacent to the sampled residential environments, including the production, use, and burning of Cu−Cr− As treated timber in New Zealand 79 and geology and industry in New Caledonia. 80,81 Cumulative exposure to trace metals has been significantly associated with health impacts such as obesity, hypertension, and type-2 diabetes. 82 Cao 83 reports that cumulative risks for children's trace metal exposures must be considered, rather than simply considering each trace metal individually.…”

Development of a bioavailability‐based risk assessment framework for nickel in Southeast Asia and Melanesia

“…A study on Australian test species in field‐collected natural waters from Australia (Peters et al 2018 ) concluded that the existing approaches for normalization of ecotoxicity data to local water chemistry conditions (e.g., Nys et al 2016 ) were also appropriate for tropical species. Additionally, ongoing work in New Caledonia focuses on the development of an EQS in a region defined by high background Ni concentrations in fresh waters (e.g., tap water concentrations in the order of 10 µg/L; St‐Jean et al 2018 ). The New Caledonia EQS project consists of a multistep approach and includes not only quantifying the background Ni concentrations but also expanding to selecting tests for waters with a wide range of bioavailability potentials of Ni, identifying and isolating native species for testing, and ultimately performing toxicity tests to generate reliable toxicity threshold values applicable to the area.…”

NiONP-Induced Oxidative Stress and Mitochondrial Impairment in an In Vitro Pulmonary Vascular Cell Model Mimicking Endothelial Dysfunction

“…Anthropic activities such as openpit mining and the natural erosion of soils in New Caledonia has led to the atmospheric emission of Ni particles and, in particular, to the emission of nickel oxide nanoparticles (NiONPs) due to the hydrometallurgical process used to extract Ni [8,9]. Previous studies have revealed significant contamination levels in the New Caledonian population and have shown elevated levels of Ni in the lungs of nickel refinery workers [10,11]. Moreover, cardiovascular diseases were found to be more prevalent among those workers [12].…”