Absolutely not. I would be most suspicious of them, especially if they say “God will reward you for your good hearts”, as the one that fluttered through my door last week did. Promises to deliver your clothes directly to the needy of the developing world are often as empty as the rails of registered charity shops that are suffering from this murky business. Just after Christmas, a Mencap shop in Ashton, near Manchester, reported that it was being forced to shut down because unscrupulous individuals taking donations from kerb collections. With all the clothes going into the pockets of the con artists — and most likely being flogged at car boot sales — there was none left for the real deal. “It’s a scam,” said one of my favourite websites, Rip Off Britain (rip-off.co.uk). To curb this outrage, you could curtain-twitch until the scoundrels come back to pick up the loot and then report the vehicle’s registration number to the police.

Of course, there are legitimate charities. Salvation Army and Help the Aged are some of the most committed door-to-door collectors of old garb. But the bags they post through the letterbox are usually emblazoned with the charity logo and the leaflet will have a registered charity number. “Check online first that it is genuine, and if in doubt, phone us and ask whether you should trust the collectors,” said my obliging local Salvation Army outpost. Should we be worried that those doing the genuine collections pilfer the best items? Apparently not. The collectors are local volunteers, not middlemen, with charitable tendencies and robust consciences.

I want guilt-free slap. Can you recommend a range of organic make-up?

Until recently it was assumed that green types would be best left with flowers and face paints as their only adornments. Anything more might hide their inner beauty and suggest a shamefully consumerist lifestyle. Now a new generation of glitzy green goddesses demands mineral-based mascara and preservative-free lippie. There is an argument that some chemicals and preservatives are no bad thing, keeping your products in tip-top condition, and therefore avoiding the environmental implications of buying more. I’ve met plenty of organic obsessives, including Josephine Fairley, author of Feel Fab Forever (Kyle Cathie, £15.99), who mix and match trustworthy brands and green alternatives.

But if you’re keen for a change — and please tell me how you get on — I’d make Dr Hauschka your first port of call (drhauschka.co.uk). Awarded best natural make-up range at the Beauty Awards last year, its products are jolly good and certified as natural by a German regulatory body (bronzing powders cost from £18; eyeliners from £14). There are also ranges by Lavera (soorganic.com) and the beauty industry favourite Jane Iredale (thenaturalstore.co.uk) that skip parabens, artificial fragrances and other man-made chemicals. Since they are devoid of life-giving properties, remember that products may need to be chucked out earlier than usual. My Organic Pharmacy shimmer cream (theorganicpharmacy.com; £29), which has been brightening my skin since autumn, has developed a mouldy crust. A case in which a hint of green is not a good look.

For Anna's e-mail address and her EcoBlog, go to www.timesonline.co.uk/ecoworrier

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