The 'Keeping Up With the Kardashians' star has revealed she examines how sensitive her skin is to materials by rubbing a small sample of the cloth on her body and waits to see if she comes out in a reaction, according to her interior designer Martyn Bullard.
The star shared the news with a behind the scenes clip of her home to her website kourtneykardashian.com, which sees the creative mastermind unveil Kourtney's secret to selecting the decor.
In the video he said: "She[Kourtney] will get a piece of fabric and then she'll rub it all over her face, then rub it on her chin and then her neck to see if she will be allergic to it."
Meanwhile, the mother of three - who has sons Mason, six, 18-month-old Reign and three-year-old daughter Penelope with her former husband Scott Disick - has revealed since becoming a mother she has realised the dangers in cleaning products and has begun to use "non-toxic" replacements to protect her and her brood.
She explained: "After having kids, I have slowly become aware of the harmful chemicals in everyday cleaning products. I have since discovered so many great non-toxic cleaning products that are effective, but made with safe and natural ingredients. There are so many harmful chemicals, found in many cleaning products, that have been linked to asthma, cancer, reproductive disorders and hormone disruption. I look for products that are free of artificial colors, cancer-causing parabens, chemicals like ammonia (which can irritate the skin, eyes and lungs) and phosphates, which are harmful to the environment.
"The kitchen is such an important place to keep clean because so many of the family's meals are prepared there, so keeping it safe from chemicals is a top priority. It always freaks me out when I see people spraying their counters down with tons of chemicals either right next to food or right where food is going to be cooked.
"Harsh products and fragrances can irritate my and my children's skin, so these products are very important to me, especially for towels and sheets."
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