Today, Rwanda joins the rest of the international community to celebrate World Environment Day. The annual event is an opportunity to reflect on the importance of the natural world to our collective prosperity, and re-double our efforts to protect our environment and make the world a better place for future generations. This World Environment Day, our attention is focused on air pollution - and for good reason. Poor air quality is one of the world’s most pressing environmental health threats. Today, more than 90% of people globally breathe polluted air and approximately seven million people die from air pollution-related causes every year. Furthermore, air pollution costs the global economy US $5 trillion in welfare costs annually, and ground-level ozone pollution is expected to reduce staple crop yields by 26 per cent by 2030. Despite not having large polluting industries, Rwanda is not immune to the challenge of air pollution. According to the results of a recent inventory on the sources of air pollution, Rwanda is being affected by all major pollutants but particulate matter and nitrogen dioxide are the pollutants of main concern. Data indicates that concentrations of some types of particulate matter in Kigali are elevated and, at times, above globally acceptable standards. The research indicates that vehicle emissions are the leading cause of air pollution in Kigali and other urban areas while domestic wood, charcoal cookstoves and burning in fields are the primary contributor to poor air quality in residential and rural areas. What this tells us is that we are all exposed to air pollution, and that we all have a role to play to address it. Whether you are a farmer who burns the remains of your harvest, a parent who cooks with charcoal or someone who drives a car, there is something we can all do to clean the air we breathe. If we don’t take action now, the negative health effects will only get worse. Chronic exposure to polluted air increases the risk of cardiovascular and respiratory diseases, as well as lung cancer. New research has also indicated that air pollution affects happiness, may cause dementia and could even impair cognitive ability, especially in children. Rather than spend large sums of money addressing the impacts of air pollution, let’s control the problem at its source. Doing so requires a joint effort - from the individual level to government. That’s why we are putting in place policies, laws, regulations and standards to reduce air pollution. Regular car-free days, creating green spaces, motor vehicle inspections, introduction of bike lanes, subsidies for LPG as an alternative to charcoal, vehicle and power plant emissions standards, e-mobility strategies and the recent establishment of the African Air Quality and Climate Laboratory here in Kigali are just a few examples. Forests also play a key role in purifying the air we breathe. That’s one reason Rwanda is aiming for 30% forest coverage by 2020 - a goal we are close to achieving. And while large natural forests such as Nyungwe and Gishwati and forest plantations might seem far off, we can bring the forest to our doorstep by planting trees in our gardens and public spaces. Not only do trees filter pollution from the air, such as ozone, nitrogen dioxide, ammonia, and particulate matter as well as by capturing carbon, but they also mitigate the effects of heat through evapotranspiration and the shading of the buildings and streets. Trees planted near houses and buildings need to be some distance from structures to avoid damage by crown and root systems and should focus on medium-sized broad leaved trees with deep roots which provide a high canopy index. Some of the trees we can all consider planting at home include Erythrina abbysinica (Umuko), Prunus Africana (Umwumba), Albizia gummifera (Umusebeya), Polyscias fulva (Umwungo) and Mitragyna stipulosa (Umuzibaziba). Rwandans are also encouraged to plant fruit trees which have the added benefit of improving nutrition and food security. Alongside these efforts, the government has established the first integrated pollution-monitoring system through the Rwanda Air Quality and Climate Change Monitoring Project. Financed by the Rwanda Green Fund, the project has installed eight low-cost monitors in Rusizi, Rubavu, Nyabihu, Gicumbi, Byimana, Kirehe, Kayonza and Nyagatare. It has also created a reference station at the Meteo Rwanda Headquarters in Gitega which houses high-quality equipment that collects data serving as a reference for the calibration of the low-cost monitors. By investing in data collection, we can make more informed decisions and strengthen enforcement in the areas that need it most. Let’s all continue to utilise the research and data we have, put our heads together to find innovative ways to address the problem and strive to build an environment free from air pollution, and indeed pollution of any kind. Together we can #BeatAirPollution. The writer is the Minister of Environment of the Republic of Rwanda. The views expressed in this article are of the author.