Toxic chemicals and microplastics in soil and water are fueling a global heart disease crisis — but researchers say solutions are within reach.
Review: The links between soil and water pollution and cardiovascular disease. Image Credit: daniilphotos / Shutterstock
A recent study published in the journal Atherosclerosis reviewed the links between water and soil pollution and human health.
Clean water and healthy soil are essential to human health, well-being, and the environment. Healthy soils underpin ecosystems by supporting food production, water retention, biodiversity, and carbon storage. Soil degradation is estimated to jeopardize the health of 40% of the world’s population. Moreover, as of 2021, over two billion people have lived in water-stressed regions. In 2019, illnesses related to pollution caused nine million premature deaths. Besides, pollution accounted for about 268 million disability-adjusted life years (DALYs).
Air and soil pollution significantly impacts DALYs across life stages, albeit the latter mainly affects older people. Further, water pollution drives infant mortality. Notably, over two-thirds of diseases due to pollution are noncommunicable diseases (NCDs), and cardiovascular diseases (CVDs) account for 60% of this burden. Yet, the global action plan for NCD prevention and control lacks pollution mitigation. The study also highlights that environmental factors like pollution may surpass genetic predispositions in driving NCDs, revealing a crucial gap in current health strategies.
Soil pollution results from harmful compounds, like synthetic chemicals, heavy metals, pathogens, pesticides, micro-/nanoplastics (MNPs), and plastics, primarily from mining, industries, agriculture, waste mismanagement, and fossil fuel consumption.
MNPs, an emerging contaminant, release toxic additives like phthalates and bisphenols, which disrupt cellular function and exacerbate cardiovascular risks. The paper emphasizes that MNPs act as carriers for other toxic chemicals, amplifying their harmful effects on cardiovascular and metabolic health. While less visible than air pollution, water and soil pollution remains critical. As such, the present study reviewed the interplay between water and soil pollution and human health, emphasizing CVDs.
Main effects of soil contaminants on human health, indicating the organs or systems affected and the contaminants causing them. PCBs, polychlorinated biphenyls; PBDEs, polybrominated diphenyl ethers; PFAS, per- and polyfluoroalkyl substances; POPs, persistent organic pollutants; BTEX, refers to the chemicals benzene, toluene, ethylbenzene, and xylene. Adapted from the report of the Food and Agriculture Organization of the United Nations (created from data in the Agency for Toxic Substances and Disease Registry and Campanale et al., https://www. fao.org/3/cb4894en/online/src/html/chapter-04-3.html
Chemical Pollution
Contamination of water and soil threatens public health through toxic chemical exposure. Hazardous substances include polycyclic aromatic hydrocarbons, heavy metals, organic solvents, pesticides, and per- and polyfluorinated substances (PFAS). Heavy metals like lead, mercury, arsenic, and cadmium cause cancer, neurodevelopmental disorders, and CVDs.
Arsenic is a major cause of water-mediated deaths, while lead and cadmium are related to ischemic heart disease and hypertension. Even low exposure to heavy metals increases the risk of CVDs. Persistent organic pollutants such as pesticides, dioxins, and polychlorinated biphenyls accumulate in tissues and disrupt endocrine pathways.
Bisphenol A and PFAS are endocrine disruptors that increase the risks of CVDs, obesity, and dyslipidemia. Endocrine disruptors are also implicated in disrupting circadian rhythms and metabolic homeostasis, contributing to CVD risk.
MNPs, derived from plastic degradation, induce oxidative stress, endothelial dysfunction, and atherosclerosis. Recent human studies show MNPs accumulate in arterial plaques, increasing cardiovascular event risks.
Mounting evidence links water and soil pollutants to cardiovascular outcomes. Lead exposure is a well-known cause of hypertension and higher cardiovascular mortality. Moreover, blood levels of lead are reportedly associated with atherosclerosis in the carotid arteries in a Swedish cohort, which was also confirmed by a study in the United States (US).
Impact of chemical pollution from various sources on the global burden of premature deaths. Estimated global annual deaths by all sources of chemical pollution (A) and the disease entities being associated with these deaths (B). (C) Deaths by all chemical pollution – ranking by top 20 countries. Population-related rates of death and disability-adjusted life years (DALYs) for lead pollution as a typical soil pollutant (D) and water pollution (unsafe water source including chemical hazards) (E), listed for 20 representative countries of different WHO regions.
Ecodisruptive Causes of Water and Soil Pollution
The Food and Agriculture Organization has highlighted the critical role of soil as a carbon sink. However, climate change impacts global soil conditions, and the European Environment Agency has highlighted increased desertification risks, erosion, altered coastal soils, and decreased soil moisture due to rising sea levels. Besides, rising temperatures have serious ramifications on agricultural productivity.
Overfertilization disrupts nitrogen cycles, contributing to PM2.5 formation and CVD mortality. Excess nitrogen from fertilizers and livestock farming reacts with pollutants to form toxic particles linked to strokes and heart disease.
Deforestation driven by logging, mining, agricultural expansion, and urbanization disrupts the ecosystem, aggravates climate change, and threatens human communities and wildlife. Forests form crucial carbon sinks, and their clearance releases greenhouse gases and decreases the planet’s ability to absorb them. Deforestation also disrupts the hydrological cycle, resulting in changes in rainfall patterns, floods, and droughts and accelerating biodiversity loss.
Poorly designed cities with high traffic, limited green spaces, and industrial zones amplify pollution exposure. Urban heat islands and contaminated runoff worsen cardiovascular risks, while sedentary lifestyles linked to car-centric infrastructure compound health burdens. Additionally, inadequate waste management in urban areas leads to persistent soil and water contamination by heavy metals and hazardous chemicals, further elevating cardiovascular risks.
Communities relying on forests for cultural practices, sustenance, and traditional medicines face enormous challenges, including food insecurity, loss of livelihood, and displacement. In the Amazon, wildfires accelerate greenhouse gas emissions and biodiversity loss, further destabilizing the region's hydrological system. Further, airborne dust arises from soil disturbance through construction, unpaved roads, wind erosion from deserts, and agriculture.
Inhaled dust induces inflammation, oxidative stress, and cardiovascular and respiratory system damage. Smaller dust particles could enter the bloodstream, aggravating immune responses and CVDs. Studies have linked exposure to desert dust to a higher risk of cardiovascular and respiratory deaths. As climate change accelerates desertification, extreme weather, and drought conditions, airborne dust will likely become a significant component of air quality degradation, warranting mitigation measures.
Concluding Remarks
Water and soil pollution significantly reduces biodiversity and threatens human health and the ecosystem. Exposure to heavy metals, toxic agents, pesticides, MNPs, and plastics induces endothelial dysfunction, circadian rhythm disruption, inflammation, and oxidative stress. MNPs synergize with chemical additives, worsening cardiovascular injury through mechanisms like pyroptosis and NLRP3 inflammasome activation. Chemical pollutants could synergize with other health factors and exacerbate the burden of NCDs. Nevertheless, reducing water and soil pollution is linked to cardiovascular health benefits.
Mitigation strategies include limiting exposure to chemicals through air purification, water filtration, smoking cessation, and avoiding contaminated foods, among others. The paper emphasizes that medical interventions such as chelation therapies, including EDTA-based treatments, are effective in removing heavy metals like lead and cadmium, reducing cardiovascular risk.
Public health measures, like those successfully implemented in high-income countries to reduce lead and cadmium exposure, have significantly lowered CVD mortality. Policy initiatives like the European Commission’s Zero-Pollution Vision aim to reduce pollution to safe levels by 2050, while the EU Soil Deal prioritizes soil restoration and pollution reduction.
The EU also aims to prevent soil sealing, improve soil biodiversity, reduce desertification, and enhance soil organic carbon stocks as part of broader restoration goals. Moreover, dietary and lifestyle interventions provide protective cardiovascular effects. While pollution drives several diseases, it is preventable and not a byproduct of economic development, as high-income countries have shown that replicable, cost-effective solutions can control pollution.