The chemicals in your garage that may raise risk of incurable muscle-wasting disease that killed Stephen Hawking

Chemicals in your garage may raise your risk of the muscle-wasting condition that killed Stephen Hawking, a study suggests.

Researchers found that storing chemicals - including gasoline, weed killer, pesticides, paint, and woodworking supplies - in a garage connected to the home may be linked to the development of amyotrophic lateral sclerosis, or ALS.

The more chemicals someone had in their garage, the higher the risk of the condition that still has no known cause.

'Exposures in the home setting are an important part of the' development of ALS, said said lead study author Dr Stephen Goutman, associate director of the ALS Center of Excellence at the University of Michigan.

Storage in an attached garage of chemical products including gasoline or kerosene, gasoline-powered equipment and lawn care products were found to be the top three risk factors. Gasoline or kerosene was linked to an increased risk of 14 percent, while gasoline-powered equipment, such as a lawnmower, were linked to a 16 percent raised risk

Renowned physicist and cosmologist Stephen Hawking died aged 76 after living for more than 50 years with ALS

The CDC estimates that 31,000 Americans live with ALS; on average, 5,000 new patients are diagnosed yearly.

In the UK, the condition is also called motor neuron disease and affects about 5,000 people. 

ALS is caused by a problem with cells in the brain and nerves called motor neurones. These cells gradually stop working over time. It's not known why this happens.

Having a close relative with motor neurone disease, or a related condition called frontotemporal dementia, can sometimes mean you're more likely to get it. But it doesn't run in families in most cases.

'Screamingly high levels' of PFAS found in most US pesticides

Texas researchers found the chemicals in seven out of 10 insecticides - but six had extremely large quantities of a particularly dangerous type that has been strongly linked to cancer. 

Researchers from the University of Michigan looked at more than 600 American participants - 367 who had ALS and 255 who did not. 

Participants were given a survey about their exposure to chemicals at home, with questions about which chemicals they stored in their garage as well as whether their garage was attached to their house or separate.

Most participants reported storing several of the items in their attached garage.

After statistical analysis, they found that the storage of chemicals were significantly associated with ALS risk.

Storage in an attached garage of chemical products including gasoline or kerosene, gasoline-powered equipment and lawn care products were found to be the top three risk factors.

Gasoline or kerosene was linked to an increased risk of 14 percent, while gasoline-powered equipment, such as a lawnmower, were linked to a 16 percent raised risk.

Lawn care products were associated with a 15 percent increased risk.

Storing chemicals in a detached garage, however, did not show as strong of an association with risk.

The researchers said this may be due to the flow of air and airborne pollutants from attached garages to the living space.

'Especially in colder climates, air in the garage tends to rush into the house when the entry door is opened, and air flows occur more or less continuously through small cracks and openings in walls and floors,' said Stuart Batterman, senior author and professor of environmental health science at the University of Michigan School of Public Health.

'Thus, it makes sense that keeping volatile chemicals in an attached garage shows the stronger effect.'

About five to 10 percent of cases of ALS are inherited, according to the ALS Association, while the other 90-95 percent have no genetic link. 

The study was published in the journal Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration.

Amyotrophic lateral sclerosis (ALS): Details of fatal disease there is no cure for

What is it? 

Amyotrophic lateral sclerosis (ALS) is a neurogenerative disorder which impacts the nerve cells in the spinal cord and the brain, according to the Mayo Clinic. It gets progressively worse and causes significant muscle control loss in people who have it. 

Treatment 

There is no cure for ALS and the disease is fatal, but it progresses at different speeds in patients. 

Symptoms

The first signs of ALS are twitching of the muscles, weaknesses of the limbs and problems with swallowing and speaking. Progressively, it deteriorates muscle control and impacts an individual's ability to breathe, move, speak and eat.

ALS symptoms correspond with where nerve cells deteriorate in each person, and could lead to issues walking, tripping, and weakness of the knees, ankles and hands.

It can also lead to problems with muscle cramps and twitching in areas including one's tongue, arms and shoulders. People with ALS have experienced untimely spells of laughter, tears and yawns, as well as changes to one's thinking process or behavior, according to the clinic.

Risk factors 

Among the risk factors researchers have established for ALS include genetics, as about 10 percent of people diagnosed with it were passed down a gene from a relative, which is called hereditary ALS, according to the clinic. Kids of people who have hereditary ALS have a 50 percent chance of having the gene.

Age is also a factor as the risk of getting the disease trends up toward the age of 75, with the most common range of people who have it between 60 and 85. In terms of gender, men are diagnosed with a higher rate of ALS prior to the age of 65, according to the clinic.

Other factors that have been linked to ALS include smoking and exposure to toxic substances. The clinic reported that military personnel have been diagnosed with ALS at a higher rate.

Causes

There is no known cause of ALS, according to the Mayo Clinic, and heredity plays a factor in a small number of cases. 

Lou Gehrig was one of baseball's preeminent stars while playing for the Yankees between 1923 and 1939. Known as 'The Iron Horse,' he played in 2,130 consecutive games before ALS forced him to retire. The record was broken by Cal Ripken Jr. in 1995 

Lou Gehrig's Disease

As well as being known as ALS, it is frequently referred to as Lou Gehrig's disease.

Lou Gehrig was a stalwart first baseman for the New York Yankees between 1923 and 1939. He was famous for his strength and durability, earning the nickname 'The Iron Horse' with a record-setting streak of 2,130 consecutive games.

In a July 4, 1939 speech on Lou Gehrig Appreciation Day at Yankee Stadium, the ballplayer famously said, 'For the past two weeks you have been reading about a bad break. Yet today I consider myself the luckiest man on the face of the earth.'

His popularity and fame transcended the sport of baseball. He died two years after his diagnosis on June 2, 1941.