Evaluation of soil contamination by heavy metals at public cemeteries in the municipality of Lages, southern Brazil

Abstract

The burial of bodies is a potentially polluting activity. Taking this into consideration, the aim of the present study was to verify the compliance of two cemeteries with environmental legislation and to quantify the concentrations of heavy metals in soils affected by burial activities. Physicochemical characterization of the soil was performed by analyzing control samples from areas near the cemeteries. Concentrations of cadmium, lead, chromium, nickel, zinc and copper were determined using high-resolution continuum source atomic absorption spectrometry. The two cemeteries had unsatisfactory properties for the retention of metal cations, with clay percentages ranging from 15.40 to 41.40% and sand percentages ranging from 28.75 to 66.85%. The control samples presented low cation exchange capacity (12.27 to 22.73 cmolc/dm³) and high aluminum (Al3+) saturation (66.74 to 90.16%). Although neither of the two cemeteries had concentrations above the limits established for the metals analyzed by Resolution No. 420/2009 of the National Environment Council, the contaminants may be leaching to groundwater due to inadequate soil characteristics.

Preliminary study of graveyard soil as a potential source of AMR - analysis of exhumation soil samples from the New Cemetery in Chełmża, Poland

“…Despite the existence of many forms of dealing with corpses, traditional burials at the cemetery are still a common practice [22,[32][33]. This may pose a sanitary and epidemiological threat [32,[34][35].…”

Could Necroleachate Be the Cemetery’s Sewage? A Panorama from Brazilian Legislation

“…The employed fabrics are made from hard-to-degrade materials and are treated with chemical binders. The wood used for coffins is usually treated with preservatives such as polyvinyl chloride, creosote, or insecticides, as well as varnishes and sealants, which release harmful toxic substances during their degradation [62,75,75,85,86].…”

Contamination of groundwater by necro-leachate and the influence of the intervening factors in cemeteries of the municipality of Lages – Brazil

“…This cemetery covers an area of 60,817 m². Regarding its pedological characteristics, its surroundings have a predominantly clay texture (38% clay and 34% sand), as well as low CEC (12.55 to 22.73 cmolc.dm -³) and high aluminum saturation (Al 3+ ), with an average of 81.24% (BAUM et al 2021).…”

“…Despite the soil texture being adequate, the values of CEC from both cemeteries are low, due to the fact that a great part of it is occupied by Al 3+ ions (BAUM et al 2021), preventing other cations, such as heavy metals, being adsorbed in the edges of clay minerals. Under these conditions, and considering that the soils of the surroundings of the cemeteries, as well as their inner areas, do not show levels of heavy metals above the MPVs, the metals originated from the process of degradation of burial materials may be leaching into groundwater, where concentrations above the MPVs were found for Cd, Cr and Ni.…”

“…Regarding the potential for influencing soil texture, the soil of the CNSP has a predominantly clayish texture, while the soil of the CCA is characterized as predominantly sandy (BAUM et al 2021). According to Üçisik and Rushbrook (1998), soils constituted by a clay-sand mixture of high porosity and high specific area, such as those found at the CNSP, maximize the retention of degradation products.…”