How Acid Rain Affects Metal Structures

Acid rain is a mixture of wet and dry deposited material that contains unusually large amounts of nitric and sulfuric acids, according to the Environmental Protection Agency. This toxic precipitation—formed when sulfur dioxide and nitrogen oxide emissions react with water, oxygen and other chemicals—can corrode metals like bronze, chip away paint and depreciate marble and limestone.

Rusted wet chains
credit: Hemera Technologies/ Images

Toxic Combination

Corrosion isn't the only effect of acid rain; remnants from deteriorated metal structures can mix with the precipitation and create more toxic forms of metal, according to an "Environmental Health Perspectives" article filed with the National Center for Biotechnology Information's PubMed Central.

Contaminated Water

Acidic water can dissolve metals in highly corrosive piping systems and may increase metal concentrations in drinking water, according to "Environmental Health Perspectives."

Declining Property Values

Just a bit of acid rain can negatively affect the worth of metal items; corrosion can sharply reduce the value of buildings, bridges, monuments and automobiles. Monetary value isn't the only concern; statues and other local or regional fixtures plagued by acid rain can diminish societal value in cherished landmarks.

Rising Maintenance Costs

The dry deposit of acidic compounds can dirty buildings and lead to higher cleaning costs. To prevent these liabilities, some automobile manufacturers use acid-resistant paint, according to the agency, which estimates these special coatings cost $5 per car.

Impact on Health

Public health can be negatively affected when acid rain corrodes metal structures, sending remnants to storm-water runoff and streams, contaminating seafood and particularly threatening those who consume fish in large quantities, according to "Environmental Health Perspectives."

Chronic renal-failure patients whose dialysis treatments contain contaminated drinking water can experience dialysis dementia and other disorders, the journal reports.

The agency's acid rain program aims to reduce sulfur-dioxide and nitrogen-dioxide emissions to control air pollution.