This may explain the source of the problem regarding FemSeven patches and the domino effect on other brands.
https://www.chemistryworld.com/news/chinese-plant-closures-disrupt-supply-chains/3009954.articleParticularly this:
'Preserving supplies
The Chinese government aims to improve air quality by forcibly closing the country's most polluting
factories, which is having knock-on effects around the world.
The crackdown has already triggered a full-fledged supply crisis.
US trade body the Household & Commercial Products Association (HCPA) has been sounding alarm bells
over a shortage of benzisothiazolinone (BIT), a widely used preservative.
US manufacturers obtain a BIT precursor, o-chloronitrobenzene, almost exclusively
from China. A few months after plants producing the substance have been closed down,
the industry is dealing with ‘complete supply destruction', says Steve Bennett, the
HCPA's senior vice president of scientific affairs.
‘This is a situation that has evolved over the past six to eight months and now we are at
a point where there is virtually no BIT – or formulations containing BIT – remaining in
the supply chain,' he says.
Bennett says formulators are switching to alternatives where possible. But BIT – which
is used in paints, cleaning products, adhesives and other consumer products – is tricky
to replace.
It has a fairly long lifetime, high utility and fewer of the skin sensitisation
concerns that keep other preservatives from being used in skin-contact products.In Europe, the substance is one of few preservatives available to the paints and
detergents industries. Here, too, the responsible trade bodies – the International
Association for Soaps, Detergents and Maintenance Products (Aise) and the European
Council of the Paint, Printing Ink and Artists' Colours Industry (Cepe) – are on edge
over what Aise calls a ‘very fragile supply chain'.
BeaR.