日消費團體發現不銹鋼產品也會生銹

Recently the NHK News on-line reported the following:
ステンレス製の台所の流しについて、国民生活センターは、手入れを怠るとさびる製品もあるとして、消費者に注意を呼びかけています。
国民生活センターは、消費者から「ステンレス製の流しがさびた」という相談が、この６年間に全国で１２３件寄せられたことから、主なメーカー４社の製品を対象に４週間、一定の間隔で水とみそ汁程度の濃さの食塩水をかける商品テストを行いました。
その結果、水では変化がありませんでしたが、食塩水では４社中３社の製品でさびができたということです。
国民生活センターは消費者に対して、ステンレス製の流しを使う際は、塩分を含む汚れなどを長期間放置しないよう注意を呼びかけています。
また、製品に含まれる「クロム」や「ニッケル」などの金属の量によっても、さび方に違いが出たことから、ステンレスの種類を確認することが選ぶ際の判断材料の１つになるとしています。
国民生活センターの松本浩司さんは、「さびにくいステンレスも、使い方しだいではさびることがあるので、手入れを怠らないでほしい」と話しています。
また、業界団体のキッチン・ガス工業会は、「手入れの重要性について、これまで以上に周知するとともに、ステンレスの種類について情報提供するかどうか今後検討したい」としています。
(試譯文)
Regarding the kitchen sink made from stainless steel, the National Consumer Affairs Center of Japan was appealing to consumers for caution after noting that there were products which would rust if care was neglected.
The National Consumer Affairs Center of Japan, in relation to the discussion with customers about "the sink made from stainless steel rusted", had brought into focus 123 items in six years in the whole country to do test on the products of four main makers in which water and the salt solution at the concentration of about the miso soup were poured in at fixed intervals for four weeks.
Although there was no change in water, it was said that in salt solution rust popped up in the product of the three companies out of the 4 companies.
The National Consumer Affairs Center of Japan appealed to consumers that when using the sink made from stainless steel, be cautious not to neglect the salt containing dirt in letting it stay for a long period of time.
Moreover, the rust that came out would differ having regard to the quantity of the metal, such as "chromium", "nickel", etc. which was contained in a product; it was supposed that at the time of making a choice, the kind of stainless material would be one factor to consider when doing the judgment .
Mr. Koji Matsumoto of the National Consumer Affairs Center of Japan was saying that "Since the stainless steel which does not rust easily may also rust depending on the usage, I want that there was no neglect in using it with care."
Moreover, the related trade organization the Kitchen Guth Industry Association said that "About the importance of using care, from now on the above is well-known; in future I would like to examine whether information dissemination would be carried out regarding the different kinds of stainless metal."

So it is the salt in the dirt that affects the chromium and nickel content inside the stainless metal.