Some common issues with backyard sandboxes include sand contamination, safety concerns for children, and pests or animals digging in the sandbox. Additionally, sandboxes can attract insects and other pests, such as ants and flies, which can be a nuisance for both children and adults. Sandboxes can also become a breeding ground for bacteria and other harmful microorganisms if not properly cleaned and maintained. It is important to regularly clean and sanitize the sandbox to prevent these issues from occurring. Additionally, it is important to monitor children while they are playing in the sandbox to ensure their safety.