China's quarantine administration said on Thursday that its Shenzhen bureau has detected harmful pine wood nematodes in 13 batches of wooden packages of US-imported goods this year.
All the substandard wooden packages were produced by six heat treatment manufacturers with official US certificates, said the Administration of Quality Supervision, Inspection and Quarantine (AQSIQ).
The local quality supervision official in Shenzhen also discovered harmful living organism in another 10 batches of wooden packages from the United States among the total 70 batches sampled between July 14 and August 23, according to the administration.
The proportion of substandard wooden packages from the US, which stood at 15.38 percent according to the sampling, was much higher than the figures for the European Union, Republic of Korea, Japan and Canada, said the AQSIQ.
The Chinese administration believed that either the heat treatment manufacturers or the US exporters were behind the problems in the US wooden packages.
It added that labels on some wooden packages could not be clearly recognized as the letters imprinted were vague, indicating some exporters might have used fake labels.
The administration said the captured packages had been improperly treated according to quarantine requirements, and it had urged local officials to tighten supervision over US-imported wooden packages.
A day earlier, the administration said it found a recent cargo of 21.6 tons of frozen potato slices imported from the United States was not up to quality standard concerning carbonyl and acidity levels.
The Chinese administration had destroyed the goods according to relevant laws and regulations. It had notified the US side of the incident and asked the latter to investigate into the matter.