Open Access

Article

Article ID: 3197

Emerging contaminants in Colombian water sources and their oncological risk: A QSAR modeling approach

by Giovanny Jurado-Gamez, Patricia Eugenia Velez-Varela, Vanessa Jurado-Davila

Journal of Toxicological Studies, Vol.3, No.2, 2025;

This study investigates the presence and potential oncogenic risks of pharmaceuticals as emerging contaminants in aquatic environments in Colombia. These substances enter ecosystems primarily through human and veterinary use, and are discharged via sewage and wastewater systems. A selection of pharmaceuticals found at high concentrations in effluents across different Colombian regions was identified based on a comprehensive review of indexed scientific literature. To assess their potential health impact, a Quantitative Structure-Activity Relationship (QSAR) approach was applied to predict the toxicological behavior of each compound based on its molecular structure. The findings indicate that while many parent pharmaceuticals show relatively low carcinogenic potential, several degradation products and metabolites exhibit structural features linked to carcinogenicity. Functional groups such as nitrosamines, phenols, and epoxides—known for their genotoxic effects—were identified in some metabolites, suggesting they may damage DNA, induce mutations, and promote cancer development. These results emphasize the importance of considering both parent compounds and their transformation products in environmental health risk assessments. Long-term exposure to such contaminants may represent a significant oncological risk, reinforcing the need for stricter monitoring and predictive toxicology models like QSAR to support environmental and public health policies.

Open Access

Case Report

Article ID: 3031

Case report: Levosimendan as a possible inotropic drug for acute aluminum phosphide toxicity

by Meray Medhat Shokry Zaghary, Salah Eldeen Tag Elsir Ali, John Medhat Shokry Zaghary, Bishoy Reyad GabAllah Issa, Nourseen Effat Abd El_Gaber Ajamy

Journal of Toxicological Studies, Vol.3, No.1, 2025;

Background: Aluminum phosphide is a severe poisoning that can lead to death. Easy availability with no specific antidote is the leading cause of the higher mortality with it. Case report: The study represents a case report of a 5-year-old male who came after oral ingestion of aluminum phosphide and presented with vomiting, sleep, low blood pressure of 80/20, and a regular and rapid pulse of about 140 per minute. Gastric lavage was done rapidly with 3 bottles of paraffin oil, then 1 bottle was given every 1 h for 4 cycles. Complete laboratory investigations were performed for the patient, such as arterial blood gas, liver enzymes, electrolytes, full blood count, and renal function, which showed normal function except for metabolic acidosis with overcompensated respiratory alkalosis. The patient was transferred to the pediatric intensive care unit, where we gave a dose of 1 mEq sodium bicarbonate per kg with N-acetylcysteine 150 mg/kg in 100 mL of 5% glucose for 2 h under coverage of hydrocortisone and Avil. Antiemetics and proton pump inhibitors were given regularly every 12 h. After discussion with the pediatric specialist, the ejection fraction of the child by echocardiography was low, about 40%, and levosimendan was recommended to be given to the patient. The patient was given a bolus dose of 6 µg/kg over 10 min, followed by an infusion of 0.1 µg/kg/min with excellent response for 48 h. After admission for one week, the patient recovered completely, the ejection fraction became 55%, and the patient was discharged safely to home. Conclusion: Acute accidental exposure to AlP, either accidentally or suicidally or rarely homicidally, presents a significant threat to human life with many toxic effects, especially on the heart. Levosimendan is a drug that is used in decompensated heart failure and can be used as an inotropic agent in acute AlP toxicity.

Open Access

Article

Article ID: 2115

Bioaccumulation of metals and metalloids in soils and in the earthworm Hyperiodrilus africanus from uncontrolled landfills in Kinshasa, Democratic Republic of the Congo

by Marie-Madeleine O. Akonga, Honoré M. Mutwejile, René V. Gizanga, Jean S. Kayembe, Dieudonné E. Musibono, Fernando P. Carvalho, John Poté, Emmanuel K. Atibu

Journal of Toxicological Studies, Vol.3, No.1, 2025;

To better understand the ecological impact of pollutants from uncontrolled landfills and to assess the potential risks they pose to terrestrial ecosystems and public health, soil samples were collected from uncontrolled landfills in three municipalities of Kinshasa and analyzed for 17 metals and metalloids (including metals Fe, Zn, Mn, Cu, Pb, Cr, Co, Sn, Ni, Cd, Sc, Ag, Mo, and Hg, and metalloids Se, As, Sb) using ICP-MS and AAS. The following decreasing order of elemental concentrations was generally observed in soils: Fe > Zn > Mn > Cu > Pb > Cr > Co > Sn > Ni > Cd > Se > As > Sb > Sc > Ag > Mo > Hg. The Geoaccumulation Index (Igeo) and the Enrichment Factor (EF) indicated very severe to extremely severe soil contamination by metals, with high enhancement of Cu, Zn, As, Ag, Cd, Sb, Pb, and Hg concentrations. Furthermore, several ecotoxicological indices, such as the Potential Ecological Risk Index (RI), highlighted serious soil pollution, particularly in the samples from the landfill receiving industrial waste at Limete municipality. Therefore, the use of these soils from uncontrolled landfills for fertilization of agricultural fields, as farmers currently do, poses a serious risk to public health. Concentrations of metals and metalloids were determined also in the earthworm Hyperiodrilus africanus, collected in the same areas, and the earthworm bioaccumulation factor (on a dry weight basis) displayed values greater than one in most samples and up to 15.3. This bioaccumulation of metals and metalloids from the soil suggests that earthworms can be used as a bioremediation agent for contaminated soils. Based on the results from this research, several recommendations are made to improve the pollution control and to protect public health.

Open Access

Review

Article ID: 2772

Heavy metals in the environment: Detection techniques and toxicity

by Imene Hadj Henni

Journal of Toxicological Studies, Vol.3, No.1, 2025;

Heavy metals are characterized by their relevance, toxicity, and capacity to accumulate in the natural environment. Therefore, their emission into the air can cause long-term environmental hazards. In addition, they can be transported in the atmosphere over long distances and deposited in regions far from the emission location. Among the pollutants currently implicated by their toxicity in the environment, we can cite, in order of importance, mercury, cadmium and lead, which are currently a matter of concern. Mercury is transported over long distances in the atmosphere, and its biotransformation into toxic methylated compounds and bioaccumulation in the trophic chain have made it a major pollutant. Cadmium, which is relatively rare and is mainly found in ores, is considered one of the most toxic metals. Its accumulation in different types of sediment and its capacity for remobilization constitute particularly worrying risks. Finally, although Pb is less toxic than Hg and Cd, it is very abundant in its natural state and is used in large quantities in industry, which makes this ubiquitous toxin a permanent threat to the health of populations. This review provides an analysis of the occurrence of heavy metals in the environment, including Cu, Pb, Ni, Hg, Cr, Zn, Fe, and Cd, their toxicity potential, their impact on human health, and detection technologies using Field-Effect Transistor (FET) sensors.

Open Access

Article

Article ID: 2201

Protective role of exercise and curcumin on regional BMD and oxidative stress induced by lead

by Valiollah Dabidi Roshan, Sara Pouriamehr

Journal of Toxicological Studies, Vol.3, No.1, 2025;

The current study aimed to assess the impacts of 8-week non-pharmacological strategies on the regional bone mineral density (BMD) and the oxidative stress among rats regarding lead acetate (Pb) exposure. Randomly, we divided 40 rats into 5 groups: Pb, SHAM, curcumin+Pb, exercise+Pb, and curcumin+exercise+Pb. The rats received Pb (20 mg/kg), curcumin solution (30 mg/kg), and/or treadmill running 5 times/week during an eight-week research protocol. The femur and tibia regional BMD were measured by the DEXA system. Additionally, blood collections were performed to measure oxidative/antioxidant markers. It was demonstrated that BMD lessened significantly in the femur and tibia of rats exposed to Pb, particularly in their distal epiphysis. Whereas TBARS remarkably elevated, TAC dropped in the Pb group. On the other hand, the curcumin supplementation alone did not affect BMD, while performing the weight-bearing exercise resulted in a significant elevation of BMD in spongy tissue (i.e., the proximal and distal epiphysis of femur and tibia bones), specifically a combination of exercise and curcumin consumption protocols. Therefore, exercise training and consuming curcumin supplements may provide osteoprotective benefits against Pb-induced toxicity.

Open Access

Article

Article ID: 2187

Tracking heavy metal pollution and potential ecological threats in soils around Mfamosing cement plant, Nigeria

by Udiba U. Udiba, Blossom U. Ejah, Abo I. Nta, John Ama, Amah J. Etim, Ekom R. Akpan, Ekpo E. Antai

Journal of Toxicological Studies, Vol.3, No.1, 2025;

This study, conducted from June to December 2022 around the Mfamosing cement plant in Akamkpa, Nigeria, evaluated soil pollution status and potential ecological risks posed by heavy metals using an Atomic Absorption Spectrophotometer (Model AA-6800, Japan) after wet digestion. The ranges of lead, cadmium, mercury, arsenic and chromium concentrations (mg/kg) were: 9.11–84.73, 0.21–9.94, 0.64–0.78, 4.63–5.92, 8.25–37.23 respectively. The mean soil metals concentrations were below US-EPA maximum permissible limits and Dutch soil intervention values, cadmium being the only exception. The high spatial variations reflecting decreased metal levels with increasing distance from the cement plant suggest the cement plant may be responsible for the elevated soil metal concentrations. Metals contamination factors correspond to contamination status ranging from low contamination to very high contamination. Index of geo-accumulation (Igeo), revealed that Farms 1, 2, 3, and 4 ranged from unpolluted to strongly polluted. Ecological risk factor revealed that the metals pose a range of low to high potential ecological risk to other components of the environment. Given these findings, metal speciation analysis is strongly recommended to better understand the mobility, bioavailability, and toxicity of the contaminants. This would provide essential insights into potential uptake by crops, ecological transfer, and leaching risks, thereby guiding more targeted environmental management and remediation strategies.