Which of the following is a disadvantage of using emulsifiable concentrates?

Using emulsifiable concentrates (ECs) indeed comes with certain disadvantages, one of which includes phytotoxicity and flammability. Phytotoxicity refers to the potential harmful effects these chemicals can have on plants, which can lead to crop damage or reduction in plant health when misapplied or used in inappropriate conditions. This is especially critical in agriculture where non-target species may be affected by the pesticide, leading to economic loss and environmental concerns.

Flammability is another concern with emulsifiable concentrates, as many of these formulations contain organic solvents that can easily ignite. This poses significant safety risks during storage, handling, and application, especially in warm or dry conditions where the risk of fire is heightened.

In contrast, the other options do not accurately reflect the primary concerns associated with emulsifiable concentrates. While they can have effective concentrations of active ingredients, it is not uncommon to encounter formulations specifically designed for potency. The toxicity to humans varies by product, and many are formulated for safety when used according to label guidelines. The necessity of dilution is also a standard procedure with various types of formulations and does not inherently represent a disadvantage unique to emulsifiable concentrates. Thus, phytotoxicity and flammability significantly encapsulate the risks involved in their use.