Low-level environmental exposure to lead and renal adverse effects: A cross-sectional study in the population of children bordering the Mbeubeuss landfill near Dakar, Senegal

Abstract

This study deals with the health effects within a child population, neighbouring a landfill. After detecting metals in soil and air samples collected in the surroundings of the landfill and in a control site, we have studied: (i) levels of lead (Pb) and exposure biomarkers in blood and urine, (ii) oxidative stress biomarkers and (iii) renal injury by applying a set of early effect biomarkers. Levels of Pb were higher in the exposed site (i.e. 1129 mg/kg and 640 ng/m3 in soil and air samples, respectively) versus those in the control site (i.e. 14.3 mg/kg and 9.3 ng/m3 in soil and air samples, respectively). Pb impregnation and levels of delta-aminolevulinic acid in urine were influenced by the living site that shows the prevailingly alarming situation in the Mbeubeuss landfill. Malondialdehyde changes indicated Pb-induced excessive production of reactive oxygen species. Lactate dehydrogenase activities and proteinuria were found to be higher in the children living in the exposed site. These evidences may reveal the usefulness of these two effect biomarkers to monitor the kidney injury entailed by relatively low-environmental exposure to Pb. Overall, these results show that the Mbeubeuss landfill constitutes a real source of environmental and health risk, be it living or working on site, of the surrounding population, predominantly for children.

Lead Exposure and Oxidative Stress: A Systematic Review

“…MDA concentrations were signifi cantly higher in subjects with higher BLLs in all the studies, with a positive correlation between BLLs and MDA concentrations in the studies by Siddiqui et al ( 2002 ), Ahamed et al ( 2008 ) and Cabral et al ( 2012 ), ( r 2 < 0.392, p < 0.01; r = 0.77, p < 0.05 and r = 0.37, p < 0.05, respectively).…”

“…Additionally, 2 studies evaluated the GSSG/ GSH ratio. One of these found it to be elevated in the children living in the urban area compared to those living in the rural area (Diouf et al 2006 ), while the other study did not fi nd an association between GSSG/GSH ratio and BLLs (Cabral et al 2012 ).…”

“…Among these, the studies by Siddiqui et al ( 2002 ) and Ahamed et al ( 2008 ) identifi ed a negative correlation between BLL and GSH levels ( r = −0.32, p < 0.05 and r = −0.31, p = < 0.05, respectively). Three studies did not fi nd signifi cant changes in GSH levels with increase in BLLs (Ahamed et al 2006 ;Jin et al 2006 ;Cabral et al 2012 ). Additionally, 2 studies evaluated the GSSG/ GSH ratio.…”

“…Almeida Lopes et al case groups in which participants had not been diagnosed with a disease (2.36 ± 2.7 μg/dL; Table 3 ) (Wieloch et al 2012 ). The most frequently used biomarkers for Pb-induced OS were as follows: GSH (Siddiqui et al 2002 ;Ahamed et al 2006Ahamed et al , 2008Ahamed et al , 2011Diouf et al 2006 ;Jin et al 2006 ;Cabral et al 2012 ), MDA (Siddiqui et al 2002 ;Ahamed et al 2006Ahamed et al , 2008Ahamed et al , 2011Jin et al 2006 ;Cabral et al 2012 ;Wu et al 2013 ), SOD (Jin et al 2006 ;Diouf et al 2006 ;Ahamed et al 2008 ;Martinez et al 2013 ;Wieloch et al 2012 ;Wu et al 2013 ), CAT (Ahamed et al 2006(Ahamed et al , 2008(Ahamed et al , 2011Wieloch et al 2012 ;Martinez et al 2013 ), and GPx (Diouf et al 2006 ;Jin et al 2006 ;Ahamed et al 2008 ) (Table 3 ).…”

“…LPO was assayed by measuring the formation of MDA in 6 studies (Siddiqui et al 2002 ;Ahamed et al 2006Ahamed et al , 2008Jin et al 2006 ;Cabral et al 2012 ;Wu et al 2013 ) and the formation of TBARS in 1 study (Ahamed et al 2011 ). MDA concentrations were signifi cantly higher in subjects with higher BLLs in all the studies, with a positive correlation between BLLs and MDA concentrations in the studies by Siddiqui et al ( 2002 ), Ahamed et al ( 2008 ) and Cabral et al ( 2012 ), ( r 2 < 0.392, p < 0.01; r = 0.77, p < 0.05 and r = 0.37, p < 0.05, respectively).…”