According to patents filed at the US Patent and Trademark Office, Apple might be working on smell sensors for a variety of uses within healthcare. One such patent points to a sensor that could monitor blood sugar levels by analyzing sweat particles in the air.

The two sensors could also be used to detect pollution or carbon monoxide, or help prevent exacerbation of respiratory conditions, reports MobiHealthNews.

Apple submitted the patent applications in late 2018, and it was first spotted by Apple Insider last week.

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Two different sensors are described in the two patents. These sensors would work together: One would use lights and photodetectors to see particles in the air and the other would be an array of ionic liquid sensors that could actually detect smells. The device could get help from machine learning algorithm to distinguish between different smells.

The patents also talk about incorporating the sensors into devices that are portable, meaning they could be smartwatches, tablets or phones. The sensors could have a number of possible applications, some of which are related to health, according to the patents.

“Gas sensors can help the mobile electronic device to detect various environmental gases such as carbon dioxide, carbon monoxide, ozone, volatile organic compounds (VOCs) and the like,” the patent says. “Particulate air pollution is shown to have consistent association with illness exacerbations in people with respiratory disease as well as the rise in the number of death cases resulting from respiratory and cardiovascular disease among older people.”

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The second patent filed by Apple hints at applications for monitoring blood sugar.

“The ability to smell various flavors when combined, for example, with photo recognition can open a new horizon to smart device applications. The new applications may be in a number of areas including health, safety, security, networking and other areas. For example, in the health and safety areas, a smell-enabled (e.g., e-nose) smart communication device may be able to alert users about dangerous levels of gases such as carbon monoxide, natural gas and other toxic and/or hazardous gases, or measure compounds in human sweat and alert the user about his sugar levels, for example,” the patent said.