Minimal health impact from exposure to diet-sourced cadmium on a population in central Jamaica

Abstract

Elevated concentrations of naturally occurring Cd have been found mainly in the bauxitic soils of central Jamaica at levels up to 100-1,000 times higher than typical worldwide averages. Some food crops cultivated on these soils absorb significant amounts of Cd. Autopsy studies of kidney Cd concentrations confirm elevated human exposure, and some long-term residents in central Jamaica exceed the general population average by a factor of two. Diet studies have ascertained that a population in central Jamaica is at risk of being exposed to Cd levels in excess of the Provisional Tolerable Weekly Intake (PTWI) set by the WHO of 7 μgCd/kg bodyweight/week, and the EU TWI of 2.5 μgCd/kg bodyweight/week. Elevated levels of urine cadmium (U-Cd) and beta-2 microglobulin (β2-MG) concentrations were confirmed with a strong correlation between soil Cd and the U-Cd. Also, higher β2-MG concentrations (>200μg/g creatinine) were found in the population with U-Cd concentrations greater than 2.5μg/L. While this identification is often taken to indicate impairment in the reabsorption capacity of the renal tubules leading to renal disease, there is no evidence in the mortality records of enhanced deaths in central Jamaica compared with the general population resulting from renal disease or diabetes related complications. The highest median age of death in the island is found in Manchester, the parish with the highest average Cd concentration. While we have identified a possible Cd linked renal dysfunction, significant indications of morbidity are not present in the general population.

Role of fruits, grains, and seafood consumption in blood cadmium concentrations of Jamaican children with and without Autism Spectrum Disorder

“…To our knowledge, there are no previously published reports regarding cadmium in blood, urine, or hair of Jamaican children; however, there are published reports suggesting high levels of cadmium in Jamaican soils, particularly in areas near central Jamaica (Howe et al, 2005; Lalor, 2008; Wright et al, 2010). The mean level of cadmium in Jamaican soils was found to be 14.3 times greater than the guidelines set for safe levels of cadmium in soil used for agriculture in Canada (Howe et al, 2005).…”

“…Previous studies have reported a positive association between cadmium levels in soil and an increase in urinary cadmium concentrations in adults (Wright et al, 2010). Moreover, high levels of cadmium present in agricultural soil near central Jamaica allow accumulation in crops grown there (Lalor, 2008).…”

“…Concentrations in soil are ubiquitous and exceptionally high in certain parishes, with some greater than 900mg/kg (Lalor, 2008; Wright, Rattray, Lalor, & Hanson, 2010). These levels drastically exceed the critical limits, values above which concentrations cause the soils to be considered inappropriate for any human use, which range from 0.3–2.0mg/kg (Lalor, 2008).…”

“…Thus, increased exposure in those who consume locally grown foods is a concern (Howe et al, 2005). A study conducted in Jamaica by Wright et al (2010) showed a positive association between cadmium soil levels and urinary cadmium levels, with a 3.25 times increased risk of urinary cadmium greater than 2.5μg/g for those in high/very high soil cadmium concentration areas compared to those in low/medium concentration areas, after adjusting for creatinine levels (Wright et al, 2010). Sediment in streams in Jamaica near soils with high cadmium levels can also have noticeable concentrations (Knight, Kaiser, Lalor, Robotham, & Witter, 1997).…”

Strengthening Analytical Support in Agricultural Research

“…Analytical support has played a critical role at least in four areas of agricultural and interfacing research. They include (i) soil fertility evaluation and management in the context of augmenting soil fertility through the input of plant nutrients from external sources including mineral and organic fertilizers (Dahnke and Olson 1990;Black 1993;Mills and Jones 1996;Sahrawat and Wani 2013); (ii) monitoring and assessment of crop, food, and other natural resources' base quality (Chaney 2012;Sahrawat et al 2010;Sahrawat and Wani 2013); (iii) selection and breeding of nutritious food crops (Graham et al 2007;Ashok Kumar et al 2013); and (iv) interfacing of human health and environmental quality (WHO 2002;Johnson et al 2007;Chaney 2012;Christou et al 2014;Sahrawat 2013;Wright et al 2010), which has greatly increased in recent years.…”