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A sensor made with gold nanoparticles can detect lung cancer in a patient’s breath and may offer a diagnosis before tumors show up on an x-ray, Israeli scientists said on Sunday.

The device, which the developers say would be cheap enough for everyday use by family doctors, detected lung cancer with 86 percent accuracy and may offer a way to screen for a disease not usually diagnosed until it has spread and is no longer curable.

It uses sensors based on gold nanoparticles to detect specific compounds — volatile organic compounds (VOC) — that lung cancer patients have in high levels in exhaled breath.

Breath testing is already recognized as a way of linking specific VOCs in exhaled breath to a certain medical conditions. In 2006, researchers found dogs could be trained to smell cancer on the breath of patients with 99 percent accuracy.

Hossam Haick, one of the scientists working on the sensor, said he hoped it could soon allow doctors to have a simple test at hand to screen people during routine appointments.

“Conventional diagnostic methods for lung cancer are unsuitable for widespread screening because they are expensive and occasionally miss tumors,” Haick and colleagues wrote in Nature Nanotechnology.

“This device is not at all expensive. The whole idea in this development was to devise something very sensitive, and very cheap and very portable,” Haick, of the Technion-Israel Institute of Technology in Haifa, told Reuters.

Lung cancer kills 1.3 million people a year and is the leading cause of cancer death across the world. Only 15 percent of patients live more than 5 years, in part because the disease is usually diagnosed so late.

The device developed by Haick and his colleagues is a nine-sensor array consisting of gold nanoparticles combined with different organic groups that respond to various VOCs released by lung tumors.

They tested 56 healthy people and 40 patients who had been diagnosed with lung cancer using conventional methods.

They found the sensor could distinguish the breath of lung cancer patients from the of the control group with more than 86 percent accuracy.

Haick said the patented device needed to be more rigorously tested and obtain approval from drug licensing authorities before it could go into production.

“I would say that could take three to five years,” he said.

Various other methods exist to measure VOCs, including a breath test using color spots, but existing techniques are often expensive, slow and sometimes require the breath to be concentrated or dehumidified first.

Young football players and other athletes face the risk of major heat injury and illness if they push themselves too hard in hot weather, warn sports medicine experts.

“Football might get the most attention for severe heat-related injuries and illnesses, but the risk in other sports is very real,” Michael F. Bergeron, a youth-sports heat stress expert and co-author of the American College of Sports Medicine consensus statement, said in a news release.

“Teaching coaches the warning signs of heat illness would be a huge step toward prevention. But it’s not enough. Coaches need to progressively introduce practice duration and intensity, as well as the uniform and any protective equipment, so that young athletes can safely adapt,” Bergeron said.

“Long gone are the days of refusing players water or using heat as a strategy to ‘toughen up’ a player. Unless the coach wants a collapsed athlete — or worse — on the field, it’s just not acceptable. All athletes need to be closely monitored for signs and symptoms of developing heat illness, and participation should immediately stop and medical attention should be promptly sought at the earliest point of recognition,” he added.

Heat-related causes account for the majority of indirect deaths in high school sports in the United States, according to the National Center for Catastrophic Injury Research. Heat stroke and other heat illnesses occur in a variety of athletes, including cross-country runners and wrestlers who train in heat-retaining rubber suits in order to lose weight before an event. Even members of marching bands have heat injury and illness risks similar to those of athletes.

The American College of Sports Medicine offers these guidelines for coaches:
Don’t hold practices between noon and 4 p.m., which are typically the hottest hours of the day.
In extremely hot weather, hold practices indoors or limit outdoor practices to lighter walk-through sessions.
Increase the number and length of rest breaks in the shade and give athletes plenty of opportunities to drink sufficient fluids.