Household bleach contains sodium hypochlorite. When it meets an acid, such as white vinegar or a toilet descaler, it releases chlorine gas, which irritates the eyes and airways, sometimes badly enough to land people in hospital. Mixed with ammonia, it forms other toxic gases called chloramines. France's health and safety agency has warned about homemade weedkillers combining bleach and vinegar: never mix cleaning products.
Chlorine on its own is fairly gentle. But when it combines with urine, sweat and other grime from swimmers, it forms chloramines, which cause stinging eyes and that classic 'chlorine smell'. A well-kept pool barely smells at all. Shower before you swim and never pee in the water.
Muscle mass slowly shrinks with age, putting independence at risk. But in 1990, a study had nursing home residents aged 86 to 96 train their legs for eight weeks: their strength more than doubled. Muscle responds to training at any age. Getting up from a chair without using your hands is already an exercise.