Longueuil, the metropolis of the South Shore with its many boroughs such as Saint-Hubert and Greenfield Park, is home to a wide variety of retail businesses and restaurants. These facilities are particularly vulnerable to ant infestations, as the food premises meet all the conditions sought by the colonies: warmth, humidity and easy access to food. We were recently contacted by the owner of a delicatessen in the Vieux-Longueuil sector who had been noticing the presence of ants in the bakery section and in the back storeroom for several weeks. The situation directly threatened the health compliance of the establishment.
Initial assessment and identification
Trade inspection is subject to specific constraints: it must intervene without compromising the food safety of the products on sale or disrupting the business of the trade. Our technician made an after-hours visit, which allowed us to inspect all critical areas without hindrance: under the shelves, behind the refrigerators, in the cracks in the concrete floor, and at the junctions between the walls and the tiles.
The species identified was the Argentine ant (Linepithema humile), an invasive species known to form interconnected supercolonies that can cover large areas. Its presence in a food store is particularly worrying because it is attracted to a wide variety of foods and spreads quickly from one place to another. Unlike other species, the Argentine ant has only one queen per nest but develops satellites that make complete elimination more demanding.
Processing adapted to the business context
Taking into account the food environment, the methods have been carefully selected to comply with the regulations in force in food shops. We favored the use of non-volatile bait gels applied in fine drops in cracks, behind baseboards and under fixed equipment. This type of product is formulated for use in the food environment: it does not contaminate preparation surfaces and remains confined to targeted application areas.
At the same time, an inspection of the exterior perimeter made it possible to locate the main nest in a crack in the concrete on the façade of the building, at the level of the foundation. This outdoor nest was treated by direct injection of liquid insecticide. Outdoor bait stations were then installed along the façade to intercept the workers before they entered the store.
Our technicians also caulked the entry points identified during the inspection: an expansion joint at the bottom of the façade, two cracks at the wall-floor junction in the storeroom, and the electrical cable passages entering from the back of the building. This caulking is essential to prevent new workers from other satellites of the supercolony from returning to the same access routes after treatment.
Results and monitoring
The presence of ants in the trade decreased significantly from the first week after treatment. The bait gel worked well: the workers carried the substance to the queens, causing a gradual collapse of the inner colonies. This elimination phase usually lasts one to three weeks depending on the size of the colony and the number of satellites present. It is normal to observe a slight increase in activity in the very first few days after the bait is applied, as the workers seek to consume more before mortality gradually sets in. At the follow-up visit three weeks later, no ants were visible in the bakery section or in the storeroom.
Our anthill destruction page describes in detail all the techniques we use depending on the type of infestation and establishment. For reference, you can also consult this achievement in a similar context and this file on a large-scale intervention. Our team of exterminators in Longueuil is available for regular inspections adapted to the requirements of the food sector. Nova Extermination operates throughout the South Shore with a rigorous approach that respects the health standards in effect for food businesses.