There's nothing like an unexpected cockroach sighting to turn grown men and women into squealing messes. How did it get in? Does it have an army of cockroach mates back from whence it came (and where is that, exactly)? And let's not even get started on the joys of a full-scale infestation.
Unfortunately, it's unlikely you'll ever be completely rid of cockroaches in your home, and cockroach killers can be toxic to humans and pets as well as insects. So how do you make sure you keep the roaches under control while keeping your household safe?
CHOICE no longer reviews pest control for cockroaches.
Cockroach killers can be poisonous if ingested, and some of their chemicals can accumulate and remain in our bodies for years.
The best way to avoid a child or pet accidentally ingesting cockroach killers is to prevent roaches in the first place: keep your home clean, take out the bins often and store food in sealed containers. If that's not possible or that particular horse has bolted, pick the safest cockroach killer you can.
The best way of finding out about the toxicity of a cockroach killer is by paying attention to the signal heading at the top of the product label – it gives you a warning as to how poisonous the product is.
- No signal heading means the product is relatively safe to use.
- CAUTION means the product is a low to moderate hazard, and could cause irritation to the skin or eyes.
- POISON is very hazardous and can cause poisoning if it enters the body.
- DANGEROUS POISON means the product is extremely hazardous – just a small amount can cause poisoning or even death if it enters the body.
Exclusion zones can be a useful way of keeping children and pets safe from cockroach killers. Since cockroaches like closed, dark spaces, you can target the insecticide in areas that have limited access to babies and pets, such as ground-level cupboards, under the sink, and behind the fridge.
There are three main types of cockroach killers: surface sprays, baits/traps and knockdown sprays.
Surface sprays offer preventative, long-term control. Their active ingredients tend to be synthetic pyrethroids, which interfere with the roaches' nerve function, causing paralysis and eventually death. Some also contain an insect growth regulator, which works to inhibit the lifecycle of the roach.
- Surface sprays are best applied to cracks, crevices and gaps, as well as inside rubbish bins, cupboards, drawers and shelves.
- Don't treat surfaces where food is handled, or that are washed regularly, with surface spray.
- If treating food storage areas, ensure food is sealed and removed first, and only replace it once the treatment has dried.
- Always wash hands after use.
Baits and traps
Baits and traps also provide long-term cockroach control, but can be more effective if used with a surface spray. The active ingredient generally used in baits and traps is Indoxacarb, which blocks sodium channels in an insect's nervous system, leading to dehydration and death.
- Place them in corners and along edges where cockroaches travel.
- Don't contaminate baits or traps with surface or knockdown sprays, as this will repel the cockroaches and make the baits/traps ineffective.
Knockdown sprays, which also tend to use synthetic pyrethroids, target individual cockroaches and provide a quick response. They're not all created equal, though, and not all will stop a roach in its tracks – some are more effective on little German cockroaches than the big American dudes.