| Keywords | Year | Strength | Begin | End | 2011~2021 |
| waste water contaminant | 2011 | 5.8322 | 2012 | 2016 |
|
| sludge | 2011 | 2.714 | 2013 | 2014 | |
| groundwater | 2011 | 3.8897 | 2014 | 2015 |
|
| soil | 2011 | 3.9651 | 2012 | 2013 |
|
| gas chromatography | 2011 | 5.5128 | 2017 | 2018 |
|
| liquid chromatography | 2011 | 5.0599 | 2012 | 2013 |
|
| occurrence | 2011 | 3.3525 | 2014 | 2015 |
|
| reproduction | 2011 | 3.6266 | 2015 | 2016 |
|
| exposure | 2011 | 5.3182 | 2013 | 2017 |
|
| behavior | 2011 | 4.1375 | 2012 | 2017 |
|
| risk | 2011 | 3.0886 | 2016 | 2017 |
|
| emerging contaminant | 2011 | 5.5128 | 2017 | 2018 |
|
| sulfamethazine | 2011 | 3.2135 | 2017 | 2018 |
|
| sulfamethoxazole | 2011 | 4.9619 | 2018 | 2021 |
|
| Carmazepine | 2011 | 4.7312 | 2017 | 2021 |
|