It is important to have the latin name for the plant rather than the common name. Some plants are known to cause skin irritations for some individuals. Locate these plants away from sidewalks and paths so people aren't as apt to brush against them. In the case of potential skin irritation, wash thoroughly with soap and water the skin areas that may have come in contact with the plant. In many cases, washing immediately will greatly reduce the irritation.
Pets eating plant material can also be a cause for concern.
Unfortunately, some plants that are non-toxic to humans can be dangerously toxic to cats and dogs. Much of the literature available is based on human exposure rather than domestic animals. Local veterinarians will have information on pet poisoning. Poison control centers can also provide information. Remove any plant parts remaining in the mouth.