You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

The Procrustean bed of EU food safety notifications via the Rapid Alert System for Food and Feed: Does one size fit all? Previous reports demonstrated wide variations in contributions by EU Member States (MS) to the Rapid Alert System for Food and Feed (RASFF) especially for border notifications, emphasising that MS with major entry points play a vital role in ensuring that EU food imports meet EU standards. To further explore the variation this paper aimed to examine notification practices among MS by comparing the levels of detection as a function of the total food imported and population. RASFF notifications issued between 2003 and 2007 were analysed using descriptive statistics and network analysis for differences in notification practice between MS. Major variations in contributions to the RASFF database were observed, which did not correlate with MS size or population. For the key contrast of ratio: 'border: non-border notifications', variations between 7%:89% were observed for the average monthly contributions and, import tonnage per border notification revealed up to 129-fold differences between MS. In conclusion, wide variations in food safety practice exist between MS, including both number and type of contributions to the RASFF database, with some MS being relatively highly active in the key class of border notifications. These findings should inform EU food safety enforcement policies and practices; and central resource allocations.
{"Chemical": []}