Optical Brighteners
I'm currently using Almat Non Biological washing powder and liquid, and I use about 50-75ml per wash (powder), as it tends to froth up, especially when doing hot washes at 60 degrees, If i use 100ml or more, I tend to get a suds lock during the interim spin of my Beko washer.
This has optical brighteners in it, which I don't find I'm allergic to. I tend to be itchy to strongly scented powder detergents, these fragrances stick to clothes and can be a cause of skin irritations.
I find Almat Non Bio powder lightly scented, has a classic washing powder smell. you could try using less powder per wash? About a heaped tablespoon should be enough, remember as long as you have a soft sudsy liquid, you know that you have used enough to catch the dirt and enable thorough rinsing. I have used Persil Non Bio Powder loads of times before with no problems, unless they have changed the formula and made it stronger on stains.
Its a shame they don't do a Non Biological Colour Powder detergent, that doesn't have optical brighteners or bleach in it, as you could use this for colours and add some Ecover Powder Bleach for Whites.