Chemicals should only be used as a last resort. If there is no alternative it is essential to use them responsibly and sparingly so that you affect beneficial wildlife as little as possible, for example, it you have tried unsuccessfully every other way of controlling snails and slugs and feel slug pellets are the only remaining option, you should use the following method.
Make a slit down one side of a plastic water bottle and bend the edges back. Scatter pellets inside and hall bury the bottle among the plants under attack. The slugs and snails will crawl into the bottle, eat the pellets and die. Ensure the pesticides are out of reach of small children, who may think the brightly colored pellets are sweets. The pellets should be also kept away from the soil so they cannot contaminate it. The bodies of the slugs and snails, which are now full of pesticide, are contained in the bottle to be disposed of safely where birds or other predators cannot reach them.
When spraying chemicals, ensure that all pets and children are kept well away from the area – even if the label says the chemicals will not harm them. To avoid harming beneficial insects spray on a dull and windless day – they will be less active than on a hot sunny one. If you have pond fish, make sure there is absolutely no spray drift over the water, as fish are extremely sensitive to any contact with chemicals.
Wear some protective clothing including goggles and gloves and wash away immediately any accidental splashes on bare skin using lots of cold wirier.
Keep separate watering cans and spray guns that are reserved solely for chemical use and label them so there is no risk of confusion.
Other pests which are easily treatable by this method include whitefly, red spider mite, leatherjackets and scale insects.
If you are not exactly a do it yourself type of person, you may be better off by hiring a professional pest control firm to rid your garden of pests, just like you would want to find qualified building trades contractors to install new doors and windows in your home.