DI S PATC H E S | RESOURCES be worth between $235 billion and $577 billion worldwide. So what accounts for the decline of insects? For Sánchez-Bayo, the answer is what he calls “agricultural intensification” — the elimination of all trees and shrubs that normally surround the fields, leaving behind plain, bare fields treated with synthetic fertilizers and pesticides. Not surprisingly, Sánchez-Bayo has called for changing agricultural practices to ones that preserve habitat and reduce the use of synthetic fertilizers and pesticides — points echoed in the literature, which also singles out urbanization as an obvious culprit. Another factor has since joined the ranks of insect killers: climate change. It threatens to change the delicate web of connections between insects, plants and other animals, interrupting the breeding cycles of insects and destroying their habitat with no escape, while denying other animals, especially birds, of food (in insect form) when needed most. At the same time, climate change could
alliance between the two would be beneficial for both.
9. Medical Isotopes
More than 30 million medical diagnostic procedures annually, comprising 80 per of all diagnostic nuclear medicine procedures, use technetium-99m, the unstable radioactive form of technetium, the world’s first artificially produced element of the Periodic Table. It also occurs in very small amounts in the Earth’s crust. Technetium-99m is an ideal radioactive tracer, because its decay releases readily traceable rays that can be used to monitor hearts in real time or pinpoint tumours without accompanying harmful rays. At the same time, its relatively short half-life of six hours means patients injected with
Technetium-99m is used in 80 per cent of all diagnostic nuclear medicine procedures. Shown here is the first technetium-99m generator.
Biology professor Dave Goulson says insects pollinate about three-quarters of the crop types grown by humans, a service estimated to be worth between $235 billion and $577 billion worldwide.
serve as food for other animals, cycle nutrients through the soil, help decompose organic matter, control pests and pollinate. According to Goulson, they pollinate about three-quarters of the crop types grown by humans, a service estimated to 46
also boost the populations of “insect pests” that crowd out economically viable insects while harming human food crops. Pulp science fiction often conjures up wild scenarios of insects lording over humans, but current trends suggest that an
technetium-99m as part of a radiopharmaceutical serum won’t have to suffer long periods of exposure while undergoing diagnostics. Described by World Physics as the “workhorse isotope” of nuclear diagnostic medicine, technetium-99m is especially effective in detecting various cancers, among other diseases. Technetium-99m derives from molybdenum-99, a radioisotope produced by nuclear fission of enriched uranium, or by adding a neutron to molybdenum-98, a process rife with costly inefficiencies deemed insufficient to meet demand when compared to the primary method. This reality has left the complicated task of producing molybdenum-99 to six government-owned nuclear reactors SPRING 2020 | APR-MAY-JUN
© ADAM HURLEY - DREAMSTIME.COM / BROOKHAVEN NATIONAL LABORATORY
growing body of scholarship studying the causes and effects of and remedies for declining insect populations, with perhaps no more an authoritative result than a recent survey of 73 studies. This review of the existing literature finds more than 40 per cent of insect species are declining, with a third endangered. With the total mass of insects falling by 2.5 per cent annually, and with extinction rates eight times that of mammals, birds and reptiles, insects could vanish within a century. “It is very rapid,” Francisco SánchezBayo from the University of Sydney, Australia, told The Guardian. “In 10 years, you will have a quarter less, in 50 years only half left and in 100 years, you will have none.” The consequences of this dynamic will be nothing less than catastrophic, leading to collapse of nature itself. Not everybody buys their rhetoric, but it is hard to overstate the significance of insects, which, along with other invertebrates, perform multiple functions. They
