Phosphorus losses compound with each step in the food chain—from plants to animals to us. Shifting your diet towards the plants at the base of the food chain reduces these losses. Also, animal manure is a major source of phosphorus pollution. This is mainly because animal feeding operations frequently produce too much phosphorus-laden manure for the surrounding land to assimilate. This phosphorus is transported to surrounding water bodies by rain, snowmelt, wind and irrigation.

Generally, the less meat and dairy you consume, the smaller your personal phosphorus footprint. Some animals are more “phosphorus efficient” sources of food than others. Meat from pigs and bovines (e.g. cows) is especially inefficient and their manure is the biggest problem. Here’s a rough rubric you can use:

Grains/fruits/vegetables > milk > tree nuts > mutton/goat > eggs > poultry > pig > bovines.*

Moving your diet leftwards will improve your phosphorus footprint. Also, many bottled and canned sodas, ice teas and coffees contain phosphoric acid as an ingredient. Avoiding these can reduce your phosphorus footprint.

Food waste is phosphorus waste. Food can be wasted at many points in its supply chain: at the farm, in transit to the warehouse, in transit to the store, at the store, at home, and at restaurants. In the US and Canada, the biggest share of food waste happens at homes and restaurants. In the US alone, a staggering 35% of all food goes unsold or uneaten (source: ReFed). Rightsizing your portions and being careful in grocery shopping can reduce this waste.

You can also support organizations that sell “ugly” produce. Ugly produce refers to blemished or unusually shaped produce that retailers don’t like to sell for strictly cosmetic reasons. Some stores and organizations also specialize in collecting excess prepared and perishable foods from grocery stores to provide food for those in need. Supporting these with your donations is another way to help.

Yard waste and food waste both contain phosphorus that can be recovered and reused via composting. Many municipal programs offer compost bins or green waste pickups, but if not, compost or vermicompost bins and piles are easy to construct and maintain yourself, so long as you have an outdoor space. The compost can be used in gardens and potted plants around the house, perhaps to grow more food!

Lawns typically don’t need added phosphorus after establishment, so it is best to avoid applying additional phosphorus to your lawn, especially in the winter when it might be dormant or drought-stricken. When applying fertilizer, we recommend using slow-release products from recycled sources and making sure to sweep up any fertilizer that might have been spilled onto hard surfaces, such as driveways and sidewalks, so it isn’t washed away. Avoid overwatering. You can recycle phosphorus back into the soil by leaving your lawn clippings on the grass after mowing, but keep the clippings off the lawn and street where they can be swept up in stormwater and sent to nearby waterbodies. To mitigate against nutrient discharges from your property, you can landscape the perimeter with swales, filter strips, or buffer strips. And you might even consider getting rid of your lawn entirely – think of the time you’ll save!

Dead leaves contain phosphorus and release it as they decompose. Especially in northern cities, leaf litter can contribute most of the total dissolved phosphorus to local watersheds in the winter, when it is conveyed by snowmelt. Street-side trees are especially problematic in this regard. Keeping leaves off the street and, ideally, raking and composting them to create new soil for the spring, is an easy way to reduce their phosphorus impacts.

If you aren’t connected to a sewer system and use a septic tank instead, make sure that it’s well maintained. Poorly maintained septic systems are a major concern in certain watersheds, as that waste contains phosphorus at very high levels, among other harmful constituents. Regular inspections and pumping are important, as is keeping the drain free of items that might clog it. Drain fields should be kept clear of deeply rooting plants that might cause structural damage, and anything that might compact the soil above them (e.g. parked cars) should be kept away.

Did you know that your pets poop? Did you know that their poop (and yours) contains phosphorus? While there’s not much you can do about urine, which contains phosphorus, you can pick up your pet’s solid waste and ensure it is properly disposed of before it washes away.

Herbicides and pesticides, such as glyphosate and iron phosphate, can contain phosphorus. When these wash off your property and into stormwater, they can be conveyed to lakes, rivers, and streams. It’s best not to use them at all, but if used, they are best used sparingly. Even in cities that treat stormwater, the added phosphorus load adds expense to treatment.

Timber harvesting operations can increase soil erosion, which delivers phosphorus to nearby waters, by developing roads through forests and chopping down trees. In addition, wastewater produced in converting trees to useful products contains phosphorus that must be removed before discharge. Finally, paper, pulp and forestry products themselves contain phosphorus. By using only what you need, reusing what you can, and recycling or composting paper after you are done with it, you help reduce these impacts. As with everything else, reduced use is better than recycling. Paper can only be recycled so many times before its quality degrades.

In a win for the phosphorus sustainability community, voluntary and, in some cases, mandatory bans on phosphates in laundry and dishwasher detergents have been in place in the US and Canada for some time and have proven very effective. However, owing to the voluntary nature of some of these bans, phosphate-containing laundry and dishwashing detergents are still available on the market and should be avoided for home use. For an easy way to spot P-free detergents, look for the Safer Choice logo on products.

In addition, there are other types of phosphate detergents that are still in use for other applications, such as car shampoos and cleaners—including at your local car wash—and heavy-duty cleaners, such as TSP (trisodium phosphate). The shampoo on your hair might even contain phosphates, which help shampoos lather. Whether these go down your drain or are washed off your sidewalk, they add gratuitous phosphates to the environment.

Though it may not seem intuitive, taking a yearly trip to your nearest household hazardous waste collection point and drop off items such as automobile additives or degreasers, pool chemicals, paint, and lawn chemicals can improve phosphorus recycling. Wastewater from homes typically goes to wastewater treatment plants that yield two products: treated sewage sludge (called biosolids) and water. About half of our biosolids are landfilled, which wastes phosphorus, and half are used to fertilize crops and gardens, provide landfill cover, and restore ecosystems–great ways to recycle phosphorus. However, these biosolids can be contaminated with toxic chemicals that come, in part, from our households. When you dump these down your drain or toilet, you are contaminating the waste stream, making biosolids more expensive to treat to standards and their use less viable. Contact your municipality for more details on what’s accepted by its household hazardous waste program.

Whether it’s an HOA rule, a municipal ordinance, a local infrastructure investment, or a state / provincial or federal regulation— rules shape our phosphorus footprints. Some HOAs, for instance, require that lawns are overseeded and herbicide-treated, thereby increasing the urban phosphorus footprint. Municipalities might issue bonds to pay for composting programs, street sweeping, or needed upgrades to stormwater and wastewater treatment systems that can help contain phosphorus. State /provincial and federal regulations set water quality standards that affect who can discharge how much phosphorus into local waterbodies. By becoming phosphorus-aware and using your vote, you can influence decision-makers to support the cause.