The common chemical DEHP—found in carpets, flooring, upholstery and wires—and the industrial chemical PCB (polychlorinated biphenyl) 153—still found in foods despite a global ban—were the main causes for a decline in sperm quality.

The antiseptic compounds known as quats affect our mitochondria, the energy centres in our cells, and interrupt estrogen signalling, which could lower our fertility levels.

A woman drinking at least one sugar-sweetened sodaevery day is 25 per cent less fertile, and it has an even bigger effect on the man, whose fertility levels drop by an average of 33 per cent.

What are they?
Pesticides are chemicals used to control pests ranging from bacteria and fungi to insects, plants and rodents. Sold as sprays, liquids, sticks, powders, balls and foggers, they work by deterring, incapacitating, killing or otherwise discouraging pests.

Where can you find them?
Surveys show that the majority of us maintain a home arsenal against a variety of house and garden pests—from weed killer to flea collars and moth balls—and use an average of three to four products a year.1 Indeed, the US Environmental Protection Agency (EPA) states that 80 percent of most people's exposure to pesticides occurs indoors, and measurable levels of up to a dozen pesticides have been found in the air inside homes.2

Besides the many pest control products you probably have under your sink, pesticide residues in food (especially fruit and vegetables), bedding, carpets, furniture and household dust are other possible sources of exposure to these chemicals in the home.

Sperm motility—the ability of the sperm to move and fertilise an egg—is almost halved by the waves, and men who keep a cell phone by their body for two hours or more every day could be the most affected.