Impact of Industrially Affected Soil on Humans: A Soil-Human and Soil-Plant-Human Exposure Assessment

Bioaccumulation of heavy metals in bean planting (Vigna unguiculata L. WALP) and evaluation of the potential risk to human consumption

Beans are one of the most important legumes for human consumption. However, its cultivation in soil contaminated with metal(loid)s may harm the human food chain. We aimed to investigate the accumulation and transfer of macro- and microelements from the soil to cowpea grains. In addition, soil pollution rates and health risks associated with grain consumption were assessed. Soil and grain samples were collected from plantations close to a landfill and a highway in the city of Campo Grande, Central-West Brazil. The quantification of As, Cd, Cr, Cu, Fe, Mg, Mn, Mo, Pb, Se, V, and Zn in the bean grain and soil samples of cowpea cultivation was carried out by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The pollution index, bioaccumulation coefficient, estimated daily intake, carcinogenic and non-carcinogenic risk were calculated. The concentration of Cd (0.052 ± 0.001-0.069 ± 0.008 mg/100 g) and Pb (0.136 ± 0.019-0.216 ± 0.054 mg/100 g) in grains was above the maximum permissible daily oral dose. In addition, the hazard quotients (HQ) of the elements As, Cd, Pb, Se, and V were above the safety limit, surpassing HQ of 10 for As and Cd at all collection sites and the hazard index was greater than 27 for all sampling locations. The heavy metals As, Cd, and Cr present elevated carcinogenic risk (CRi), above 1.6 × 10-3 for cowpea intake of all studied locations. The proximity of the cowpea crop to the highway and the landfill contributed to the contamination of the soil and grains. These findings highlight the importance of monitoring and understanding the soil-plant-human system, especially when the environmental conditions surrounding crops are favorable to contamination, representing a major risk to public health.

Heavy Metals Accumulation in Vegetables and Its Consequences on Human Health in the Areas Influenced by Industrial Activities

The degradation of the environment due to numerous industrial practices has emerged as a major issue globally, particularly in a country like Bangladesh. The present study dispenses information about heavy metal (Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) contamination in some frequently consumed vegetables, namely, ash pumpkin, potato, bitter gourd, buffalo spinach, snake gourd, and pointed gourd grown in an industrially prone location and their repercussion on consumers' health. Proton-induced X-ray emission (PIXE) technique was used as the major analytical tool to detect heavy metal concentrations. Mean concentration and the range of Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb in vegetables were detected (4.81 ± 2.79, 2.43-10.94), (497.57 ± 258.08, 181.24-886.67), (644.49 ± 298.40, 179.56-998.78), (38.88 ± 14.31, 18.88-60.12), (58.11 ± 12.58, 42.55-84.79), (137.24 ± 48.37, 71.99-208.98), (123.31 ± 63.62, 49.97-256.09), (8.09 ± 2.69, 4.29-14.94), and (4.16 ± 2.95, 1.22-9.98) mg/kg (dry weight basis), respectively. An extreme level of heavy metal contamination in vegetable samples was notified regarding the estimated metal pollution index (MPI) and Nemerow pollution index (P) value, which underpinned the health risk values. The estimated hazard index (HI) value stipulated high risk in all varieties of vegetables regardless of age group and cadmium (Cd) was found as the major contributor. Concerning the carcinogenic risk index (CR) for single elements, the value of Co, Ni, and Cr was approximated far above the USEPA threshold risk limit (CR>1E-04). Moreover, total carcinogenic risk (TCR) for all varieties of vegetables exceeded the safety threshold value for both the age group and children, in particular, were found most vulnerable. The outshot of the present study divulged associated health risks for the population group by the heavy metals via dietary intake of vegetables.

The association between trace metals in both cancerous and non-cancerous tissues with the risk of liver and gastric cancer progression in northwest China

Liver cancer and gastric cancer have extremely high morbidity and mortality rates worldwide. It is well known that an increase or decrease in trace metals may be associated with the formation and development of a variety of diseases, including cancer. Therefore, this study aimed to evaluate the contents of aluminium (Al), arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), selenium (Se), and zinc (Zn) in cancerous liver and gastric tissues, compared to adjacent healthy tissues, and to investigate the relationship between trace metals and cancer progression. During surgery, multiple samples were taken from the cancerous and adjacent healthy tissues of patients with liver and gastric cancer, and trace metal levels within these samples were analysed using inductively coupled plasma mass spectrometry (ICP-MS). We found that concentrations of As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Se, and Zn in tissues from patients with liver cancer were significantly lower than those in healthy controls (P < 0.05). Similarly, patients with gastric cancer also showed lower levels of Cd, Co, Cr, Mn, Ni, and Zn-but higher levels of Cu and Se-compared to the controls (P < 0.05). In addition, patients with liver and gastric cancers who had poorly differentiated tumours and positive lymph node metastases showed lower levels of trace metals (P < 0.05), although no significant changes in their concentrations were observed to correlate with sex, age, or body mass index (BMI). Logistic regression, principal component analysis (PCA), Bayesian kernel regression (BKMR), weighted quantile sum (WQS) regression, and quantile-based g computing (qgcomp) models were used to analyse the relationships between trace metal concentrations in liver and gastric cancer tissues and the progression of these cancers. We found that single or mixed trace metal levels were negatively associated with poor differentiation and lymph node metastasis in both liver and gastric cancer, and the posterior inclusion probability (PIP) of each metal showed that Cd contributed the most to poor differentiation and lymph node metastasis in both liver and gastric cancer (all PIP = 1.000). These data help to clarify the relationship between changes in trace metal levels in cancerous liver and gastric tissues and the progression of these cancers. Further research is warranted, however, to fully elucidate the mechanisms and causations underlying these findings.

Appraisal of contamination, source identification and health risk assessment of selected metals in the agricultural soil of Chakwal, Pakistan

Contamination of metals in agricultural soil is a serious global threat but there are limited reports related to their risks in major agronomic areas. The current study is aimed to assess the distribution of selected macroelements and essential/toxic trace metals (Ca, Mg, Na, K, Sr, Li, Ag, Fe, Zn, Co, Cu, Mn, Cd, Cr, Pb and Ni) in the agricultural soil of Chakwal, Pakistan, in order to appraise their contamination status, source identification and probable human health risks. Quantification of the metals was performed by AAS employing aqua regia digestion method. Among the selected metals, dominant mean concentrations were observed for Ca (48,285 mg/kg) and Fe (30,120 mg/kg), followed by Mg (9171 mg/kg), K (973.3 mg/kg), Mn (399.0 mg/kg) and Na (368.9 mg/kg). The correlation study indicated strong mutual relationships among the metals as well as physicochemical properties. Multivariate analysis (PCA/CA) of the metal levels revealed their diverse anthropogenic sources in the soil. Various pollution indices indicated extremely high contamination/enrichment of Cd, followed by moderate enrichment/contamination of Ag in the soil. The HQ values for most of the metals manifested insignificant non-cancer risks. The average CR value of Cr was exceeding the safe limit (1.0E-06) for both ingestion and inhalation exposure, indicating a considerable lifelong cancer risk for the population. The results of this study will provide a better understanding related to the contamination of agricultural soil and its effects on human health and to promote effective actions to reduce the soil pollution.

What about the Arsenic? Health Risk Assessment in Canned Tuna Commercialized in Northern Spain

The incorrect labeling, as well as the bioaccumulation of heavy metals in seafood, represent a recurring problem worldwide, not only for natural resources but also for the consumers’ health. Heavy metals can be accumulated through the food chain and transferred to the final human consumer. Despite its toxicology, arsenic does not have a concentration limit on food, unlike other heavy metals like cadmium, mercury, and lead. Tuna species, with a worldwide distribution and high per capita consumption, represent a well-known toxicological issue caused by heavy metals. In this context, 80 samples of canned tuna were analyzed to check if the information contained in the label was correct and complete. Genetic identification was made by sequencing a fragment of 16S rDNA from 80 samples. For the heavy metal quantification, only those samples with the complete FAO fishing area information on the label were analyzed. Only 29 out of 80 samples presented enough information on the labels for the analysis. Some of the canned tuna commercialized in Spanish markets surpassed the safety standard levels established by the Joint FAO/WHO Expert Committee on Food Activities (JECFA) under the consumption rates of 300 g and 482 g per week. However, the carcinogenic risk (CRlim) for arsenic in all cans and all scenarios was higher than the safety levels.