Health and disease > evaluation

Use a volume of dilute hydrochloric acid that models the volume and concentration of our stomach contents. Add typical doses of a range of over-the-counter antacid preparations – powders, tablets and liquids. Monitor the changing pH with Universal indicator solution (or a pH probe). Compare the effects of different preparations and discuss the short and long-term consequences

This investigation follows the transfer of a harmless microorganism from an agar plate, via toilet paper to our hands. This models the transmission of faecal microbes after using the lavatory, and allows us to assess the efficacy of using toilet paper and of hand washing as part of our daily hygiene regime. You can use

This protocol can be used to investigate the effects of a range of substances that may have anti-microbial action. You can adapt it to see the effects of bactericides (that kill bacteria), bacteriostatic substances (halt microbial growth, such as, some bactericides at low dilutions). The method could be used to compare the efficacy of a range of antimicrobials in personal hygiene products (