Reader's Digest 3月号の記事 '50 Health Facts Your Doctor Wants You to Know' から引用します。
Vaccines can cause autism.
Myth! Some people have raised concerns that substance used in trace amounts in certain vaccines--including formaldehyde, aluminum salts, and thimerosal, a mercury-based preservative--could cause autism. But none of these substances has been shown to cause harm in the small doses used in vaccines.
"trace amounts" が分からないので辞書を引きます。
・Oxford English Dictionary: A very small quantity, especially one too small to be accurately measured.: his body contained traces of amphetamines
・Collins Dictionary: A trace of something is a very small amount of it.: Wash them in cold water to remove all traces of sand.
・Cambridge English Dictionary: a very slight amount: Traces of drugs were found in his blood
思い出しました。4年前（4/6/2015）に "trace mineral" で取り上げた "trace" と同じですね。
Vaccines can cause autism.
Myth! Some people have raised concerns that substance used in trace amounts in certain vaccines--including formaldehyde, aluminum salts, and thimerosal, a mercury-based preservative--could cause autism. But none of these substances has been shown to cause harm in the small doses used in vaccines.
"trace amounts" が分からないので辞書を引きます。
・Oxford English Dictionary: A very small quantity, especially one too small to be accurately measured.: his body contained traces of amphetamines
・Collins Dictionary: A trace of something is a very small amount of it.: Wash them in cold water to remove all traces of sand.
・Cambridge English Dictionary: a very slight amount: Traces of drugs were found in his blood
思い出しました。4年前（4/6/2015）に "trace mineral" で取り上げた "trace" と同じですね。
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