Is acid rain dangerous?

  • Date: May 14, 2022

Acid rain, or acid deposition, is any form of precipitation with high levels of sulfuric and nitric acid. These can be wet or dry and include rain, snow, fog or even dry particles. Although, this can sometimes be a natural occurrence – such as rotting vegetation or volcanic emissions – it is primarily the result of human actions such as car-use and power generation.

Is acid rain dangerous to humans?  

Whilst walking in an acid rainstorm you won’t come to any harm – acid rain is not acidic enough to burn your skin. Even swimming in more-acidic-than-normal lake would not have any effect – it would feel the same as swimming in the water of a typical lake, you would probably not be aware.

However, acid rain can have a more indirect – less immediate – effect on human health. The sulfur dioxide and nitric oxides that contributes to the formation of acid rain can affect humans more directly than the resultant acid rain. They can result in respiratory diseases, such as asthma, or make existing conditions worse. Furthermore, nitrogen oxides can also result in tropospheric or “ground-level” ozone – a gas that can be extremely harmful to human health. It can lead to pneumonia and other respiratory issues; in some cases, it can even lead to irreversible lung damage.

Is acid rain dangerous to plants and trees?

Acid rain is particularly dangerous for plants and trees. Acid rain that is absorbed into the soil can have an affect on the magnesium and calcium levels in the ground – these are vital for the healthy growth of plants and tress. Furthermore, acid rain can cause an increase in aluminum in the soil, causing water uptake of water by plants to be hindered. These conditions are clearly sub-optimal.

Trees that grow at high altitudes, such as fir trees, are especially vulnerable – they can also in contact with acidic fog and clouds which have a higher level of acid than that of acid rain. This can lead to vital nutrients being removed from their leaves and this makes them more vulnerable to infection and low temperatures, amongst other things.

Are animals affected by acid rain?

Aquatic ecosystems, and animals living in them, are thought to be the most affected by acid rain. Acid rain falls directly into lakes and streams, and this is compounded by runoff water from forests and roads. With some acidic lakes and streams having a pH of less than 5 – the typical pH is between 6 and 7 – aquatic life is inevitably affected. This can be made even more acidic, and dangerous, during episodic acidification. For example, during periods of high rainfall or during springtime snowmelts.

According to Professor Thomas Wolosz from the State University of New York the effect on the reproduction systems of the aquatic life is the main cause of animal extinction in aquatic species. Some types of fish have decreased calcium levels which affects their reproduction whilst some females fail to produce ova in an acidic body of water. Water with a low pH has increased levels of carbon dioxide – this ultimately can lead to decreased growth of aquatic species as well as deformities due to bone decalcification.

Bird life can also be affected. It is thought, according to work done by the Cornell Lab of Ornithology,  to have been cause of the decreasing population of the Wood Thrush. Calcium-rich food is needed by the female Wood Thrush to ensure their eggs are sufficiently solid. However, acid rain has led to a decrease in snail populations – one of the key calcium sources for the birds. This has led to egg defects and the resulting decline in reproduction.

Although acid rain can have a direct effect on animals – for example, breathing acid particles has been thought to lead to respiratory issues – it primarily has an indirect negative effect. Some mammals rely on fish as their food. Since acid rain leads to a reduction in populations this can have a knock-on effect to all members of a food chain. For instance, if a fish population declines it may affect the otters in the same environment who now have a decreased food sources.

What can acid rain do to buildings?

In addition to plants, animals and humans, acid rain can also have an effect on material objects such as buildings, monuments and cars. The acidity can strip paint from your car and erode the stone in statues and buildings, making their condition deteriorate more quickly. Although, not on the same magnitude as the reduction in biodiversity or potential long term affects to human-health they are still regarded as an important part of our culture nonetheless.

The bottom line

Acid rain can be dangerous for plants, animals and humans, in different ways. Although acid rain is not dangerous for humans in the short-term, the pollution that results in rain can have significant impact on respiratory health – even potentially leading to permanent damage in some cases. The impact is more widely seen in plant and animal life. Acid rain can stunt plant growth and make it more vulnerable to other factors such as low temperature. Animals, like humans, are indirectly affected – the food chain that they exist within can become altered and their food source eliminated.