Almost a third of factories worldwide were rated as "critically non compliant" with ethical and sustainability standards in the first quarter of 2017, according to a supplier audit company.
AsiaInspection said the proportion of non compliant firms rose to 30%, compared to 27% in 2016.
The audit firm uses a range of metrics including working hours, wages, quality and factory safety to score suppliers out of 10.
Working hours and wages were the areas where most violations took place.
The top performing industry was food containers and bodycare, where factories had average audit scores of eight.
The structural safety of factories gave cause for concern as it continues to deteriorate, with the percentage of compliant factories dropping to 30.5% from 37% in 2016 and 41% in 2015.
More than two thirds of factories needed to carry out remediation works while 4% were affected by critical safety risks in the short and medium term.
The industry most likely to suffer poor quality was the textile industry, where 41.7% of products fell short of the target specifications.
Over 5% of products destined for the EU contained unacceptable levels of chemicals.
"Product quality and safety remain a challenge for brands and retailers worldwide," said Sebastien Breteau, CEO of AsiaInspection. "Evolving safety regulations on multiple levels, combined with the increased consumer and media awareness, make it difficult even for established brands to continuously ensure compliance in an ever more global market."