“The impact of the second-hand clothing trade on developing countries” by Oxfam gives some insight into the importance of the second hand clothing trade which can be read in its entirety here:
http://www.bcrglobal.com/assets/downloads/research_shc.pdf
In summary, second-hand clothing:
Has clear consumer benefits, especially in countries with low purchasing power, and for poorer consumers
Is perhaps a factor in undermining local textile/clothing production and employment
Supports the livelihoods of thousands of people
Is poorly regulated and probably facilitated considerable customs fraud
Is a dominate feature of the clothing market in many sub-Saharan African countries
Companies often have recycle back programs, such as Apple, Nike and LensCrafters although donating used clothing to charitable organizations such as the Goodwill or drop-off bins are also very convenient.
wastetracking.wordpress.com 