laboratory vs sweatshop

laboratory

noun
  • A room, building or institution equipped for scientific research, experimentation or analysis. 

  • A place where chemicals, drugs or microbes are prepared or manufactured. 

sweatshop

noun
  • A factory or other place of work where pay is low and conditions are poor or even illegal. 

How often have the words laboratory and sweatshop occurred in a corpus of books? (source: Google Ngram Viewer )