Wetting refers to the dynamics of how a liquid, when deposited on a solid (or another liquid) substrate, is able to spread. This wetting of solid substrates by liquids is a basic element in many natural and commercial processes. Understanding the wetting phenomenon enables us to explain why water spreads nicely on clean glass, but does not spread on a sheet of polypropylene.

A wetting agent is a compound that causes water to spread over the surface of another material. A common observation is that the addition of a surface active agent (or surfactant) to water will enable a solution to wet.

With the regulatory arena becoming more and more restrictive, the move to water-based coatings has reached a high point and has necessitated the development of additives to assist the formulator in overcoming the required regulations. The result, however, can be the inclusion of more additives than the formulator would like to use.

An innovative technology has been developed that will give the formulator the choice to use a family of additives that are multi-functional, thus limiting the number of additives necessary to successfully produce the desired coating properties. Although these materials are wetting agents, they also serve at least one other purpose, such as being an excellent dispersant, being biodegradable or having a very low critical micelle concentration (CMC). The properties and characteristics of these products are highlighted in numerous testing regiments that follow. The materials are designated MW (multifunctional wettings agents) followed by A, B, C, D or E.

COOP, Denmark's leading retailer, with about 1,200 supermarkets, lives by the precautionary principle and has therefore removed all endocrine-disrupting chemicals from its products. This gives consumers a choice, says Malene Teller Blume.

Malene Teller Blume is compliance manager for non-food products at COOP and recently spoke at the European Consumer Organisation's (BEUC) conference on chemicals in Brussels in June.

Andrea Cupp made a serendipitous discovery when she was a postdoctoral fellow at Washington State University: While investigating how chemicals affect sex determination in embryonic animals, she bred the offspring of pregnant rats that had been dosed with an insecticide called methoxyclor. When the males from that litter grew into adults, they had decreased sperm counts and higher rates of infertility. Cupp had seen these same abnormalities in the animals' fathers, which had been exposed to methoxyclor in the womb. But this latest generation hadn't been exposed that way, which suggested that methoxyclor's toxic effects had carried over generations. . . .

Skinner and Cupp, who is now a professor at the University of Nebraska-Lincoln, published their findings in 2005. Since that paper -- which showed that reproductive effects not just from methoxyclor but also from the fungicide vinclozolin persisted for at least four generations -- the number of published articles reporting similar transgenerational findings has increased steadily. "In the last year and half there's been an explosion in studies showing transgenerational effects from exposure to a wide array of environmental stressors," says Lisa Chadwick, a program administrator at the National Institute of Environmental Health Sciences (NIEHS). "This is a field that's really starting to take off."

According to Chadwick, the new findings compel a reevaluation of how scientists perceive environmental health threats. "We have to think more long-term about the effects of chemicals that we're exposed to every day," she says. "This new research suggests they could have consequences not just for our own health and for that of our children, but also for the health of generations to come."

The NIEHS recently issued requests for applications totaling $3 million for research on transgenerational effects in mammals. Chadwick says funded studies will address two fundamental data needs, one pertaining to potential transgenerational mechanisms and another to the number of chemicals thought to exert these effects. These studies will extend to what's known as the F3 generation -- the great-grandchildren of the originally exposed animal.

N,N-Diethyl-m-toluamide, better known as DEET, has been the go-to insect repellent for more than 60 years. But DEET dissolves some plastics and inhibits the mammalian enzyme acetylcholinesterase, which is involved in neurotransmission. Scientists have faced hurdles to finding alternatives to DEET, including a lack of knowledge of which insect receptors are responsible for its repellency and the high cost of identifying and testing substitutes. As part of the search for DEET replacements, Anandasankar Ray and coworkers at the University of California, Riverside, have identified odor receptors and neurons that detect DEET and have developed a computational screening method for identifying new repellents. The researchers found that a receptor called Ir40a, which is expressed by neurons in fruit fly antennae, responds to DEET and is necessary for DEET avoidance behavior. For the computational screen, the team used shared features of DEET and other known repellents to sift through a library of more than 400,000 compounds. The researchers got approximately 1,000 hits, with about 150 from naturally occurring compounds. They then tested 10 of the compounds on fruit flies and found that eight were repellent. The team also tested four of the compounds in mosquitoes using an arm-in-cage assay that determines whether solutions at 10% concentration repel mosquitoes from treated human arms. All four compounds were effective.