This May, we celebrate Clean Air Month to educate Americans on the positive impact clean air has on their health and our environment.

Since 1970, the air we breathe has been protected from harmful pollutants that are detrimental to our health and our nation’s delicate ecosystem. Using the Clean Air Act’s authority, President Obama and the Environmental Protection Agency (EPA) have strengthened limits for particulate matter and mercury and have proposed, for the first time, to limit carbon emissions.

Scientific evidence has clearly shown that greenhouse gases like those emitted from coal-burning power plants are a leading cause of climate change. Coal-fired power plant emissions threaten the health of current and future generations and will have disastrous impacts on our economy and global stability.

Reducing carbon entering our air is a serious challenge we face today. 154 million people across the country already experience air pollution levels that are dangerously unhealthy. We’ve had our own experiences with these threats locally. The GenOn Power Plant along the Potomac River had been in severe violation of air quality standards for sulfur dioxide (SO2), nitrogen oxide (NOx), and particulate matter for years. Nearby residents complained of poor air quality caused by short smokestacks that ejected the hazardous toxins directly into the living rooms of high-rise apartment buildings. Thanks to citizen involvement and committed local officials, we were able to shut down the Potomac River Generating Station in 2012.

Despite these successes, and in the face of a growing problem nationwide, Republicans in the House and Senate continue to advance legislation that would roll back environmental standards that protect our air and water. They have consistently introduced legislation to weaken Clean Air and Clean Water standards, insist that man-made climate change does not exist, and pass wish lists for special interests that pollute our air and water masquerading as good government. Their environmental track record in recent years, if it could even be called that, is unconscionable and harms the American people.

We owe it to our constituents and our communities to protect the air we breathe and the water we drink. Congress can’t keep exposing public health to dangerous levels of mercury, arsenic, and lead and remain stewards of the abundant natural and cultural heritage passed down to us. If future generations are to remember us fondly, we need to leave them a glimpse of the world as it once was.