Objective

Vectors such as mosquitoes, flies, and ticks can spread disease with serious short and long term effects on soldiers’ health, including permanent scarring, and possibly death. Since permethrin is the only insect repellent product labeled for clothing application by the Environmental Protection Agency, permethrin-treated uniforms are a key component of the Department of Defense Insect Repellent System. However, vector species are developing a resistance to pyrethroid-based repellents, significantly diminishing protection of service members. In addition, permethrin wears off with laundering and is highly toxic to fish and other wildlife. Luna proposed to replace current permethrin-treated fabric treatment with a non-toxic mechanical insecticide fabric treatment that possesses resistance to mosquito bites.

Technical Approach

Luna explored established fabric treatment methods including dip-pad, spray, and blade application while developing the mechanical insecticide fabric treatment. North Carolina State University Entomology Department performed mosquito bioassay tests to evaluate the insecticidal, repellency, and bite resistance of the fabric treatments. In conjunction with mosquito bioassay testing, Luna tested the fabric treatments for wash durability (AATCC 135), total weight (ASTM D776), and air permeability (ASTM D737).

Interim Results

Luna developed a water-based polyurethane dispersion with reactive cross linker to generate a durable, non-toxic textile with high bite resistance. The program demonstrated that mosquito bite resistance was demonstrated, however the testing showed that the textiles were not insecticidal nor were they insect repellent. [Note although the treated fabric is not insecticidal, the additive used is still referred to as a Mechanical Insecticide (MI) for consistency from the initial proposal and reports.] The treated fabrics demonstrated bite resistance to at least 10 washes, increased the breaking strength of the fabric (ASTM D5034), and maintained breathability and drape after treatment.

The total weight increase was dependent on the fabric selection and textile application method. Future development efforts would enable application optimization and testing against permethrin treated fabrics, allowing for a direct comparison of mosquito bioassay performance.

Benefits

The absence of harmful chemicals from Luna’s MI fabric treatment adds significant environment benefits while maintaining the user safe from pesticides. Luna took measures to ensure the application method was scalable, ensuring an easy transition to larger, industrial scale setting. In addition to uniforms, the technology may also be applied to t-shirts, socks, and caps. As such, the technology is applicable to commercial markets where there is a need to replace permethrin treated clothing for civilian use.

  • Manufacturing,

  • Insect Repellants,

  • Flame Retardants,

  • Fiber,

  • Textile,