The strength of Earth’s magnetic field has been weakening for 160 years, and some scientists worry the planet’s magnetic poles may soon flip or reverse. In a recent study, researchers from New York’s University of Rochester analyzed data from as far back as the first millennium A.D. to try to understand better the magnetic field decay. They discovered a pattern of fluctuations in magnetic field direction and intensity but said it is too early to know if a full-blown pole reversal is on the horizon.

Swirling liquid iron in the Earth’s outer core generates the magnetic field that encases our planet and protects us from harmful solar radiation. If the field becomes too weak, increased radiation levels could cause increases in skin cancer.

Many scientists believe the last pole reversal took place nearly 800,000 years ago. A modern-day reversal could cause electrical grid failures and wreak havoc on navigational systems and satellites.

The weakest region in the magnetic field encompasses a large area that stretches from Chile to Zimbabwe. The University of Rochester scientists believe the birthplace of pole reversals may lie in an exceptionally dense area 1,800 miles beneath Southern Africa. This area, positioned just above the boundary between the Earth’s hot liquid outer core and the more solid, cooler mantle, may periodically sink slightly, disrupting the flow of iron and decreasing the magnetic field, the scientists said. In their research, published in Geophysical Research Letters in January, they studied magnetic minerals in African clay samples and identified a series of field fluctuations dating back to A.D. 400.

David Coppedge, a young-earth creationist and founder of the Creation-Evolution Headlines blog, believes the magnetic field will continue to decay. He noted on his website that while currents in the Earth’s core can act as a dynamo and generate a magnetic field, those currents will eventually slow down without an energy source. Coppedge suggested the magnetic field is sustained by dying residual currents formed when God first created the Earth.

Prescription for profit

Consumers often pay more for drug prescription insurance co-pays than they would if they had purchased their drugs without using insurance, according to new research from the University of Southern California.

The research showed that customers overpaid for their prescriptions 23 percent of the time, with an average overpayment of $7.69. The practice of charging a co-pay higher than the cost of a drug is called a “clawback,” because the middlemen that handle drug claims for insurance companies take back the overpayment from the pharmacy.

Unless patients ask, pharmacists often don’t tell them they could pay less if they didn’t use their insurance. Some insurers also use gag clauses to prohibit pharmacists from giving customers that information. Several states have banned such gag clauses, and Maryland, Arkansas, Louisiana, North Dakota, Georgia, Connecticut, Maine, and Texas have outlawed clawbacks altogether. —J.B.

Oil warning?

An unpublished study presented at the Endocrine Society meeting in March found that chemicals in lavender and tea tree oils may interfere with developmental hormones in young boys. The study indicated that these essential oils, popular as alternative medicine treatments and used as aromatherapy and in personal hygiene and cleaning products, could adversely affect puberty and cause abnormal breast development in boys.

“Our society deems essential oils as safe,” J. Tyler Ramsey, the lead researcher, said in a statement. “However, they possess a diverse amount of chemicals and should be used with caution because some of these chemicals are potential endocrine disruptors.” —J.B.