Water Vs Air Pollution: The Greater Evil?

Air and water pollution are two of the most pressing environmental issues facing the world today. While both types of pollution are detrimental to human health and the environment, it is difficult to ascertain which is worse. Water pollution is defined as the contamination of bodies of water, usually due to human activity, and can include lakes, rivers, oceans, groundwater, and aquifers. Air pollution, on the other hand, refers to the presence of harmful substances in the atmosphere, which can have detrimental effects on human health and the health of other living organisms, as well as the planet's climate.

Water Pollution vs Air Pollution

Water pollution's impact on aquatic ecosystems

Water pollution is defined as the contamination of bodies of water, usually due to human activity. This includes lakes, rivers, and oceans, as well as groundwater and aquifers. It can negatively impact aquatic ecosystems, which then affects humans and other organisms that rely on the water body.

Human settlements, industries, and agriculture are the main sources of water pollution. Every time it rains, fertilizers, pesticides, and animal waste from farms wash nutrients and pathogens—such as bacteria and viruses—into our waterways. Nutrient pollution, caused by excess nitrogen and phosphorus in water or air, is the number-one threat to water quality worldwide and can cause algal blooms, a toxic soup of blue-green algae that can be harmful to people and wildlife.

The agricultural sector is the biggest consumer of global freshwater resources, with farming and livestock production using about 70% of the earth's surface water supplies. It is also a serious water polluter. In the United States, agricultural pollution is the top source of contamination in rivers and streams, the second-biggest source in wetlands, and the third main source in lakes. It is also a major contributor to contamination in estuaries and groundwater.

Eighty percent of ocean pollution originates on land, whether along the coast or far inland. Contaminants such as chemicals, nutrients, and heavy metals are carried from farms, factories, and cities by streams and rivers into bays and estuaries, and from there, they travel out to sea. Marine debris, particularly plastic, is blown in by the wind or washed in via storm drains and sewers. Oil spills and leaks, big and small, also spoil our seas and consistently soak up carbon pollution from the air.

Water pollution disrupts the balance of biodiversity in aquatic ecosystems, harming fish, coral, and more. Zooplankton and macrobenthic organisms occupy the intermediate level in the food chain and are also capable of indicating changes in the aquatic environment. Some species can be used as an indicator of deteriorating water quality resulting from eutrophication or pollution.

Air pollution's impact on climate change

Air pollution is defined as the presence of substances in the atmosphere that have a harmful effect on human health as well as on the health of other living organisms. It also harms the planet's climate, often exacerbating natural calamities such as drought and flood.

Air pollution and climate change are two sides of the same coin, but they are typically addressed separately. Air pollution is linked to biodiversity and ecosystem loss, and has adverse impacts on human capital. It is also linked to increased COVID-19-related hospital admissions and mortality.

Air pollutants and greenhouse gases often come from the same sources, such as coal-fired power plants and diesel-fuelled vehicles. Some air pollutants do not last long in the environment, notably black carbon, a component of fine particulate matter (PM2.5). Black carbon, which is also emitted by cookstoves used in developing countries, is one of the largest contributors to global warming after CO2. It warms the earth's atmosphere by absorbing sunlight, thereby accelerating the melting of snow and ice.

Other short-lived climate pollutants (SLCPs) include methane, a potent greenhouse gas that is 84 times more powerful than CO2 and is a precursor to the air pollutant ozone. Ozone and black carbon affect weather processes and decrease agricultural yields, thus threatening food security.

Addressing air pollution is key to tackling the climate challenge. Lower levels of air pollution result in better cardiovascular and respiratory health for populations in both the long and short term. Reducing ambient and household air pollution can also reduce emissions of carbon dioxide (CO2) and short-lived climate pollutants, contributing to the near- and long-term mitigation of climate change.

Water pollution's impact on drinking water

Water pollution is defined as the contamination of bodies of water, usually due to human activities. It is a serious issue that poses significant risks to both the environment and human health. The impact of water pollution on drinking water sources is particularly concerning, as it can lead to dangerous health consequences.

One of the primary ways that water pollution affects drinking water is through the contamination of water sources. Human activities such as agriculture, industrial processes, and municipal waste disposal contribute to the presence of harmful chemicals, heavy metals, and pathogens in water bodies. These contaminants can seep into groundwater, reservoirs, and other sources of drinking water, rendering them unsafe for human consumption.

Agricultural pollution, for instance, is a major contributor to water contamination. The use of fertilizers, pesticides, and animal waste in farming can lead to nutrient pollution, causing an excess of nitrogen and phosphorus in water sources. This, in turn, can result in toxic algal blooms, which are harmful to both humans and wildlife. Additionally, pesticides and fertilizers can contain toxic chemicals that, when washed into waterways, pose risks to human health, especially in developing countries where regulations may be less stringent.

Industrial activities also play a significant role in water pollution. Toxic substances from factories and industrial processes can dissolve into water bodies, leading to chemical pollution. This includes the presence of heavy metals, oils, and other hazardous materials in drinking water sources. Furthermore, inadequate management of industrial wastewater can result in the discharge of contaminated water into rivers and lakes, further compromising the safety of drinking water.

The impact of water pollution on drinking water is not just limited to chemical and nutrient pollution. Microbial contamination, such as the presence of faecal matter in water sources, poses a significant risk to drinking water safety. In 2022, it was estimated that at least 1.7 billion people globally used a drinking water source contaminated with faeces. This type of contamination can lead to the spread of waterborne diseases, including diarrhoea, cholera, dysentery, typhoid, and polio, causing hundreds of thousands of deaths each year.

The consequences of water pollution on drinking water are far-reaching and underscore the importance of addressing this issue. While interventions such as water filtration and improved waste management practices can help mitigate the impact of water pollution, it is crucial to prioritize sustainable solutions that protect water sources from contamination and ensure access to safe and affordable drinking water for all.

Air pollution's impact on human health

Air pollution is defined as the presence of one or more contaminants in the atmosphere, such as dust, fumes, gas, mist, odour, smoke or vapour, in quantities and durations that can be harmful to human health. It is the single largest environmental health risk in Europe and a major cause of premature death and disease worldwide, with more than 6.5 million deaths linked to air pollution each year.

The main pathway of exposure to air pollution is through the respiratory tract. Pollutants can cause inflammation, oxidative stress, immunosuppression, and mutagenicity in cells throughout the body, impacting the lungs, heart, and brain, among other organs. Fine particulate matter (PM2.5) is of particular concern as it can be inhaled deeply into the lungs, enter the bloodstream, and travel to organs, causing systemic damage to tissues and cells. This can lead to a wide range of diseases, including stroke, chronic obstructive pulmonary disease, trachea, bronchus and lung cancers, aggravated asthma, and lower respiratory infections.

The World Health Organization (WHO) has found links between exposure to air pollution and type 2 diabetes, obesity, systemic inflammation, Alzheimer's disease, and dementia. Maternal exposure to air pollution is associated with adverse birth outcomes, such as low birth weight, pre-term birth, and small gestational age births. Children, the elderly, pregnant women, and those with pre-existing health conditions are more susceptible to air pollution-related diseases. Genetics, comorbidities, nutrition, and sociodemographic factors also impact an individual's susceptibility to air pollution.

Interventions to reduce air pollution exposure include air quality monitoring, implementing local actions to reduce pollution during high-pollution periods, and using technologies to reduce and filter pollution at its source.

Water pollution's impact on agriculture

Water pollution is defined as the contamination of bodies of water, usually as a result of human activities. Agriculture is a leading cause of water degradation, and the sector is the biggest consumer of global freshwater resources. Farming and livestock production use about 70% of the earth's surface water supplies, and they are also a serious polluter of these sources.

Agriculture's impact on water pollution can be seen in the contamination of rivers, streams, lakes, wetlands, estuaries, and groundwater. Every time it rains, fertilizers, pesticides, and animal waste from farms wash nutrients and pathogens, such as bacteria and viruses, into these waterways. This is known as nutrient pollution, and it is caused by excess nitrogen and phosphorus in water or air. It is the number one threat to water quality worldwide and can cause harmful algal blooms.

The use of pesticides and fertilizers in agriculture has a significant impact on water pollution. Pesticides can seep into groundwater or run off into surface waters, while the use of fertilizers increases the concentration of nitrates in groundwater, leading to high nitrate levels in drinking water sources. This can cause methemoglobinemia, or "blue baby" syndrome, in young children.

Agricultural practices have also led to the emergence of a new class of pollutants: veterinary medicines, including antibiotics, vaccines, and growth promoters. These move from farms through water to ecosystems and drinking water sources. In addition, agrochemicals, organic matter, drug residues, sediments, and saline drainage are discharged from farms into water bodies, further contaminating them.

Water pollution from agriculture has negative consequences for aquatic ecosystems, biodiversity, fisheries, and, ultimately, human health and well-being. It damages economic growth and the health of billions of people. To address these issues, interventions such as recycling hazardous substances, implementing policies and incentives for sustainable practices, and integrated farming systems can help reduce pollution and optimize resource use.

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